xfs: Remove the macro XFS_BUF_ERROR and family

Remove the definitions and usage of the macros XFS_BUF_ERROR,
XFS_BUF_GETERROR and XFS_BUF_ISERROR.

Signed-off-by: Chandra Seetharaman <sekharan@us.ibm.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>

fs/xfs/xfs_buf_item.c

@@ -960,7 +960,7 @@ xfs_buf_iodone_callbacks(
 	static ulong		lasttime;
 	static xfs_buftarg_t	*lasttarg;
 
-	if (likely(!XFS_BUF_GETERROR(bp)))
+	if (likely(!xfs_buf_geterror(bp)))
 		goto do_callbacks;
 
 	/*
@@ -991,7 +991,7 @@ xfs_buf_iodone_callbacks(
 	 * around.
 	 */
 	if (XFS_BUF_ISASYNC(bp)) {
-		XFS_BUF_ERROR(bp, 0); /* errno of 0 unsets the flag */
+		xfs_buf_ioerror(bp, 0); /* errno of 0 unsets the flag */
 
 		if (!XFS_BUF_ISSTALE(bp)) {
 			XFS_BUF_DELAYWRITE(bp);