path: drop redundant local-scope vars writes

path.c:98:2: warning: Value stored to 'len' is never read
        len -= off;
        ^      ~~~
path.c:99:2: warning: Value stored to 'path' is never read
        path += off;
        ^       ~~~
Signed-off-by: Dmitry Safonov <dsafonov@virtuozzo.com>
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>

criu/path.c

@@ -95,8 +95,6 @@ char *mnt_get_sibling_path(struct mount_info *m,
 		rpath++;
 
 	off = snprintf(path, len, "/%s", rpath);
-	len -= off;
-	path += off;
 
 	return buf;
 }