maint: remove gl/lib/reg*.c.diff; no longer needed

* gl/lib/regcomp.c.diff: Remove file, now that gnulib's
regcomp.c compiles regex.c with -Wno-unused-parameter.
* gl/lib/regex_internal.c.diff: This file induced a change to ensure
that the "Idx" type was unsigned and to remove a few "VAR < 0"
comparisons.  These days, it is probably fine to stay in sync with
gnulib/glibc's copies
of these files, so remove these patches, too.
* gl/lib/regexec.c.diff: Likewise.
Prompted by a report by Assaf Gordon and a suggestion from Paul Eggert.

gl/lib/regcomp.c.diff

@@ -1,65 +0,0 @@
-diff -pu a/lib/regcomp.c b/lib/regcomp.c
---- a/lib/regcomp.c
-+++ b/lib/regcomp.c
-@@ -539,7 +539,7 @@ regerror (errcode, preg, errbuf, errbuf_
-     size_t errbuf_size;
- #else /* size_t might promote */
- size_t
--regerror (int errcode, const regex_t *_Restrict_ preg,
-+regerror (int errcode, const regex_t *_Restrict_ preg _UNUSED_PARAMETER_,
- 	  char *_Restrict_ errbuf, size_t errbuf_size)
- #endif
- {
-@@ -1415,7 +1415,7 @@ calc_first (void *extra, bin_tree_t *nod
-
- /* Pass 2: compute NEXT on the tree.  Preorder visit.  */
- static reg_errcode_t
--calc_next (void *extra, bin_tree_t *node)
-+calc_next (void *extra _UNUSED_PARAMETER_, bin_tree_t *node)
- {
-   switch (node->token.type)
-     {
-@@ -2798,8 +2798,10 @@ build_range_exp (const reg_syntax_t synt
- static reg_errcode_t
- internal_function
- # ifdef RE_ENABLE_I18N
--build_collating_symbol (bitset_t sbcset, re_charset_t *mbcset,
--			Idx *coll_sym_alloc, const unsigned char *name)
-+build_collating_symbol (bitset_t sbcset,
-+			re_charset_t *mbcset _UNUSED_PARAMETER_,
-+			Idx *coll_sym_alloc _UNUSED_PARAMETER_,
-+			const unsigned char *name)
- # else /* not RE_ENABLE_I18N */
- build_collating_symbol (bitset_t sbcset, const unsigned char *name)
- # endif /* not RE_ENABLE_I18N */
-@@ -3383,7 +3385,8 @@ parse_bracket_exp (re_string_t *regexp,
-
- static reg_errcode_t
- parse_bracket_element (bracket_elem_t *elem, re_string_t *regexp,
--		       re_token_t *token, int token_len, re_dfa_t *dfa,
-+		       re_token_t *token, int token_len,
-+		       re_dfa_t *dfa _UNUSED_PARAMETER_,
- 		       reg_syntax_t syntax, bool accept_hyphen)
- {
- #ifdef RE_ENABLE_I18N
-@@ -3470,8 +3473,9 @@ parse_bracket_symbol (bracket_elem_t *el
-
- static reg_errcode_t
- #ifdef RE_ENABLE_I18N
--build_equiv_class (bitset_t sbcset, re_charset_t *mbcset,
--		   Idx *equiv_class_alloc, const unsigned char *name)
-+build_equiv_class (bitset_t sbcset, re_charset_t *mbcset _UNUSED_PARAMETER_,
-+		   Idx *equiv_class_alloc _UNUSED_PARAMETER_,
-+		   const unsigned char *name)
- #else /* not RE_ENABLE_I18N */
- build_equiv_class (bitset_t sbcset, const unsigned char *name)
- #endif /* not RE_ENABLE_I18N */
-@@ -3877,7 +3881,7 @@ free_token (re_token_t *node)
-    and its children. */
-
- static reg_errcode_t
--free_tree (void *extra, bin_tree_t *node)
-+free_tree (void *extra _UNUSED_PARAMETER_, bin_tree_t *node)
- {
-   free_token (&node->token);
-   return REG_NOERROR;

gl/lib/regex_internal.c.diff

@@ -1,25 +0,0 @@
-diff --git a/lib/regex_internal.c b/lib/regex_internal.c
-index 904b88e..61c8d9d 100644
---- a/lib/regex_internal.c
-+++ b/lib/regex_internal.c
-@@ -17,6 +17,8 @@
-    with this program; if not, write to the Free Software Foundation,
-    Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */
-
-+#include "verify.h"
-+#include "intprops.h"
- static void re_string_construct_common (const char *str, Idx len,
- 					re_string_t *pstr,
- 					RE_TRANSLATE_TYPE trans, bool icase,
-@@ -1394,7 +1396,10 @@ static void
- internal_function
- re_node_set_remove_at (re_node_set *set, Idx idx)
- {
--  if (idx < 0 || idx >= set->nelem)
-+  verify (! TYPE_SIGNED (Idx));
-+  /* if (idx < 0)
-+     return; */
-+  if (idx >= set->nelem)
-     return;
-   --set->nelem;
-   for (; idx < set->nelem; idx++)

gl/lib/regexec.c.diff

@@ -1,45 +0,0 @@
-diff --git a/lib/regexec.c b/lib/regexec.c
-index 21a8166..7762437 100644
---- a/lib/regexec.c
-+++ b/lib/regexec.c
-@@ -18,6 +18,8 @@
-    with this program; if not, write to the Free Software Foundation,
-    Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */
-
-+#include "verify.h"
-+#include "intprops.h"
- static reg_errcode_t match_ctx_init (re_match_context_t *cache, int eflags,
- 				     Idx n) internal_function;
- static void match_ctx_clean (re_match_context_t *mctx) internal_function;
-@@ -378,8 +380,11 @@ re_search_2_stub (struct re_pattern_buffer *bufp,
-   Idx len = length1 + length2;
-   char *s = NULL;
-
--  if (BE (length1 < 0 || length2 < 0 || stop < 0 || len < length1, 0))
--    return -2;
-+  verify (! TYPE_SIGNED (Idx));
-+  if (BE (len < length1, 0))
-+     return -2;
-+  /* if (BE (length1 < 0 || length2 < 0 || stop < 0, 0))
-+     return -2; */
-
-   /* Concatenate the strings.  */
-   if (length2 > 0)
-@@ -431,11 +436,14 @@ re_search_stub (struct re_pattern_buffer *bufp,
-   Idx last_start = start + range;
-
-   /* Check for out-of-range.  */
--  if (BE (start < 0 || start > length, 0))
--    return -1;
-+  verify (! TYPE_SIGNED (Idx));
-+  /* if (BE (start < 0, 0))
-+     return -1; */
-+  if (BE (start > length, 0))
-+     return -1;
-   if (BE (length < last_start || (0 <= range && last_start < start), 0))
-     last_start = length;
--  else if (BE (last_start < 0 || (range < 0 && start <= last_start), 0))
-+  else if (BE (/* last_start < 0 || */ (range < 0 && start <= last_start), 0))
-     last_start = 0;
-
-   __libc_lock_lock (dfa->lock);