perf tools: Assign default value for some pointers

Assign default value for pointers that are identified by the compiler as
non-initialized.

Signed-off-by: Martin Liska <mliska@suse.cz>
Acked-by: Ingo Molnar <mingo@kernel.org>
Link: http://lkml.kernel.org/r/5564393C.1090104@suse.cz
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/arch/common.c

@@ -61,7 +61,7 @@ const char *const mips_triplets[] = {
 static bool lookup_path(char *name)
 {
 	bool found = false;
-	char *path, *tmp;
+	char *path, *tmp = NULL;
 	char buf[PATH_MAX];
 	char *env = getenv("PATH");