Kazuhiro NISHIYAMA 0fb10074e1 Fix error when gems/src is read-only ...

When I shared srcdir as read-only in lima-vm,
`make install` causes following error:

```
Update rbs to 33813a60752624d58dfe5ae770b39bfaf29fbaf1
error: cannot open .git/FETCH_HEAD: Read-only file system
```

I cannot find any ignore option for `git checkout --detach`
when already checked out. So I add `if`.

2023-10-11 13:32:54 +09:00

..

gmake.mk

Fix error when gems/src is read-only

2023-10-11 13:32:54 +09:00

id.def

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keywords

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known_errors.def

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lex.c.src

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opt_insn_unif.def

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opt_operand.def

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separated_version.mk

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tags.mk

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