!1503 修复FindFstabItemForPath接口可能死循环问题（挑单monthly_20221018）

Merge pull request !1503 from cheng_jinsong/cherry-pick-1668043361

interfaces/innerkits/fs_manager/fstab.c

@@ -267,7 +267,7 @@ FstabItem *FindFstabItemForPath(Fstab fstab, const char *path)
 {
     FstabItem *item = NULL;
 
-    if (path == NULL || *path == '\0') {
+    if (path == NULL || *path == '\0' || *path != '/') {
         return NULL;
     }