xfs: split remote attribute code out

Adding CRC support to remote attributes adds a significant amount of
remote attribute specific code. Split the existing remote attribute
code out into it's own file so that all the relevant remote
attribute code is in a single, easy to find place.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Ben Myers <bpm@sgi.com>
Signed-off-by: Ben Myers <bpm@sgi.com>

diff --git a/fs/xfs/xfs_attr_leaf.c b/fs/xfs/xfs_attr_leaf.c
index 7f8b6c8..287c808 100644
--- a/fs/xfs/xfs_attr_leaf.c
+++ b/fs/xfs/xfs_attr_leaf.c
@@ -32,6 +32,7 @@
 #include "xfs_alloc.h"
 #include "xfs_btree.h"
 #include "xfs_attr_sf.h"
+#include "xfs_attr_remote.h"
 #include "xfs_dinode.h"
 #include "xfs_inode.h"
 #include "xfs_inode_item.h"