[XFS] Add op_flags field and helpers to xfs_da_args

The end of the xfs_da_args structure has 4 unsigned char fields for
true/false information on directory and attr operations using the
xfs_da_args structure.

The following converts these 4 into a op_flags field that uses the first 4
bits for these fields and allows expansion for future operation
information (eg. case-insensitive lookup request).

SGI-PV: 981520
SGI-Modid: xfs-linux-melb:xfs-kern:31206a

Signed-off-by: Barry Naujok <bnaujok@sgi.com>
Signed-off-by: Christoph Hellwig <hch@infradead.org>
diff --git a/fs/xfs/xfs_da_btree.c b/fs/xfs/xfs_da_btree.c
index ae4b18c..edc0aef 100644
--- a/fs/xfs/xfs_da_btree.c
+++ b/fs/xfs/xfs_da_btree.c
@@ -1431,7 +1431,7 @@
 	}
 	if (level < 0) {
 		*result = XFS_ERROR(ENOENT);	/* we're out of our tree */
-		ASSERT(args->oknoent);
+		ASSERT(args->op_flags & XFS_DA_OP_OKNOENT);
 		return(0);
 	}