compat/fnmatch: update old-style definition to ANSI
compat/fnmatch: update old-style definition to ANSI

We try to avoid touching borrowed code, but we encourage people to
write without old-style definition and compile with -Werror these
days, and on platforms that need to use NO_FNMATCH, these three
functions make the compilation fail.

Signed-off-by: Junio C Hamano <a6723cc3f76163bf7adb636a73ac3b0ceb3e6b9b@pobox.com>

destenson/git,destenson/git,destenson/git,destenson/git,destenson/git,destenson/git,destenson/git,destenson/git