libbb: code shrink supplementary group test

Recent upstream changes to file permission tests added a function
to check and cache values in the supplementary group list.

The implementation of getgroups() in the Windows port adds no
useful information beyond what can be obtained by checking the
current effective gid, which all callers of the new function
already do.  The function can be replaced with a simple 'FALSE'.

Saves 232-288 bytes.

1 files changed, 4 insertions, 0 deletions

diff --git a/include/libbb.h b/include/libbb.h
index ff4a67481..11d52c08c 100644
--- a/include/libbb.h
+++ b/include/libbb.h
@@ -1273,7 +1273,11 @@ struct cached_groupinfo {
 };
 uid_t FAST_FUNC get_cached_euid(uid_t *euid);
 gid_t FAST_FUNC get_cached_egid(gid_t *egid);
+#if !ENABLE_PLATFORM_MINGW32
 int FAST_FUNC is_in_supplementary_groups(struct cached_groupinfo *groupinfo, gid_t gid);
+#else
+# define is_in_supplementary_groups(g, i) (FALSE)
+#endif
 
 #if ENABLE_FEATURE_UTMP
 void FAST_FUNC write_new_utmp(pid_t pid, int new_type, const char *tty_name, const char *username, const char *hostname);