ext4: remove unnecessary NULL pointer check

brelse() and ext4_journal_force_commit() are both inlined and able
to handle NULL.

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

fs/ext4/namei.c

@@ -2110,8 +2110,7 @@ static int ext4_dx_add_entry(handle_t *handle, struct dentry *dentry,
 journal_error:
 	ext4_std_error(dir->i_sb, err);
 cleanup:
-	if (bh)
-		brelse(bh);
+	brelse(bh);
 	dx_release(frames);
 	return err;
 }