build: avoid some compiler warnings * lib/selinux-at.h: Use dir_fd, not dirfd, to avoid shadowing. * lib/exclude.c (fnmatch_pattern_has_wildcards): Use correct type. (new_exclude_segment, excluded_file_pattern_p) (excluded_file_name_p): Reduce scope. * lib/vasnprintf.c (decimal_point_char): Avoid warning on old-style declaration. Signed-off-by: Eric Blake <ebb9@byu.net>

--- a/lib/vasnprintf.c
+++ b/lib/vasnprintf.c
@@ -257,7 +257,7 @@
 # ifndef decimal_point_char_defined
 #  define decimal_point_char_defined 1
 static char
-decimal_point_char ()
+decimal_point_char (void)
 {
   const char *point;
   /* Determine it in a multithread-safe way.  We know nl_langinfo is