f2fs: check return value of freeze_super()

freeze_super() can fail, it needs to check its return value and do
error handling in f2fs_resize_fs().

Fixes: 04f0b2ea ("f2fs: ioctl for removing a range from F2FS")
Fixes: b4b10061 ("f2fs: refactor resize_fs to avoid meta updates in progress")
Signed-off-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

fs/f2fs/gc.c

@@ -2181,7 +2181,9 @@ int f2fs_resize_fs(struct file *filp, __u64 block_count)
 	if (err)
 		return err;
 
-	freeze_super(sbi->sb);
+	err = freeze_super(sbi->sb);
+	if (err)
+		return err;
 
 	if (f2fs_readonly(sbi->sb)) {
 		thaw_super(sbi->sb);