fixdep: constify strrcmp arguments

strrcmp only performs read access to the memory addressed by its
arguments so make them const pointers.

Signed-off-by: Nicolas Iooss <nicolas.iooss_linux@m4x.org>
Signed-off-by: Michal Marek <mmarek@suse.com>
diff --git a/scripts/basic/fixdep.c b/scripts/basic/fixdep.c
index c68fd61..5b327c6 100644
--- a/scripts/basic/fixdep.c
+++ b/scripts/basic/fixdep.c
@@ -251,7 +251,7 @@
 }
 
 /* test is s ends in sub */
-static int strrcmp(char *s, char *sub)
+static int strrcmp(const char *s, const char *sub)
 {
 	int slen = strlen(s);
 	int sublen = strlen(sub);