selinux: Fix warnings

scripts/selinux/genheaders/genheaders.c:20: warning: no previous prototype
for ?usage?
scripts/selinux/genheaders/genheaders.c:26: warning: no previous prototype
for ?stoupperx?

Signed-off-by: Alan Cox <alan@linux.intel.com>
Acked-by: WANG Cong <xiyou.wangcong@gmail.com>
Signed-off-by: James Morris <jmorris@namei.org>

scripts/selinux/genheaders/genheaders.c

@@ -17,13 +17,13 @@ struct security_class_mapping {
 
 const char *progname;
 
-void usage(void)
+static void usage(void)
 {
 	printf("usage: %s flask.h av_permissions.h\n", progname);
 	exit(1);
 }
 
-char *stoupperx(const char *s)
+static char *stoupperx(const char *s)
 {
 	char *s2 = strdup(s);
 	char *p;