cuse: fix uninitialized variable warnings

Fix the following compiler warnings:

fs/fuse/cuse.c: In function 'cuse_process_init_reply':
fs/fuse/cuse.c:288:24: warning: 'val' may be used uninitialized in this function [-Wmaybe-uninitialized]
fs/fuse/cuse.c:272:14: note: 'val' was declared here
fs/fuse/cuse.c:284:10: warning: 'key' may be used uninitialized in this function [-Wmaybe-uninitialized]
fs/fuse/cuse.c:272:8: note: 'key' was declared here

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
diff --git a/fs/fuse/cuse.c b/fs/fuse/cuse.c
index 2a2797e..e397b67 100644
--- a/fs/fuse/cuse.c
+++ b/fs/fuse/cuse.c
@@ -266,7 +266,7 @@
 static int cuse_parse_devinfo(char *p, size_t len, struct cuse_devinfo *devinfo)
 {
 	char *end = p + len;
-	char *key, *val;
+	char *uninitialized_var(key), *uninitialized_var(val);
 	int rc;
 
 	while (true) {