doc: generate manuals with makeinfo --no-split

* doc/Makefile.am (AM_MAKEINFOFLAGS): Add for --no-split option.
(find_mono.html): Remove --no-split from makeinfo invocation.
* NEWS (Documentation Changes): Document the change.
* doc/.gitignore (/find.info-1,/find.info-2): Remove entries.

Suggested by Antonio Diaz Diaz <antonio@gnu.org> in
https://lists.gnu.org/r/bug-findutils/2022-11/msg00001.html

NEWS

@@ -13,6 +13,11 @@ GNU findutils NEWS - User visible changes.      -*- outline -*- (allout)
   findutils now builds again on systems with musl-libc.
   This requires gettext-0.19.8.
 
+** Documentation Changes
+
+  When generating the Texinfo manual, `makeinfo` is invoked with the --no-split
+  option for all output formats now; this avoids files like find.info-[12].
+
 
 * Noteworthy changes in release 4.9.0 (2022-02-22) [stable]
 

doc/.gitignore

@@ -9,8 +9,6 @@
 /find.fns
 /find.html/
 /find.info
-/find.info-1
-/find.info-2
 /find.ky
 /find.log
 /find.pdf

doc/Makefile.am

@@ -26,6 +26,10 @@ CLEANFILES = find.txt find_mono.html findutils.texi_html_node.tar.gz dblocation.
 	find.txt  tmp-doc-install find_mono.html.gz
 MAKEINFOTXT = $(MAKEINFO) --plaintext
 
+# Tell makeinfo to put everything in a single info file: <package>.info.
+# Otherwise, it would also generate files with names like <package>.info-[12].
+AM_MAKEINFOFLAGS = --no-split
+
 find.txt: find.texi $(srcdir)/version.texi $(find_TEXINFOS)
 
 # find.txt is a file which we need to know how to build
@@ -51,7 +55,7 @@ find.txt: find.texi $(srcdir)/version.texi $(find_TEXINFOS)
 # This rule is derived from the generic .texi.html rule.
 find_mono.html: find.texi
 	rm -rf $(@:.html=.htp)
-	if $(MAKEINFOHTML) --no-split $(AM_MAKEINFOHTMLFLAGS) $(MAKEINFOFLAGS) -I $(srcdir) \
+	if $(MAKEINFOHTML) $(AM_MAKEINFOHTMLFLAGS) $(MAKEINFOFLAGS) -I $(srcdir) \
 	 -o $(@:.html=.htp) find.texi; \
 	then \
 	  rm -rf $@; \