fs/squashfs: Fix Coverity Scan defects

Fix control flow issues and null pointer dereferences.

Signed-off-by: Joao Marcos Costa <jmcosta944@gmail.com>
diff --git a/fs/squashfs/sqfs_dir.c b/fs/squashfs/sqfs_dir.c
index 00d2891..a265b98 100644
--- a/fs/squashfs/sqfs_dir.c
+++ b/fs/squashfs/sqfs_dir.c
@@ -34,8 +34,7 @@
 	struct squashfs_ldir_inode *ldir;
 	struct squashfs_dir_inode *dir;
 	u32 start_block;
-	u16 offset;
-	int j;
+	int j, offset;
 
 	switch (get_unaligned_le16(&base->inode_type)) {
 	case SQFS_DIR_TYPE: