ext4: release buffer when checksum failed

Commit b0336e8d (ext4: calculate and verify checksums of directory
leaf blocks) and commit dbe89444 (ext4: Calculate and verify checksums
for htree nodes) forget to release buffer when checksum failed, at
some places.

Signed-off-by: Guo Chao <yan@linux.vnet.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>

fs/ext4/dir.c

@@ -185,6 +185,7 @@ static int ext4_readdir(struct file *filp,
 					"at offset %llu",
 					(unsigned long long)filp->f_pos);
 			filp->f_pos += sb->s_blocksize - offset;
+			brelse(bh);
 			continue;
 		}
 		set_buffer_verified(bh);