un-static xfs_read_agf

CONFIG_XFS_DEBUG builds still need xfs_read_agf to be
non-static, oops.

Signed-off-by: Eric Sandeen <sandeen@sandeen.net>
Reviewed-by: Felix Blyakher <felixb@sgi.com>
Signed-off-by: Felix Blyakher <felixb@sgi.com>
diff --git a/fs/xfs/xfs_ag.h b/fs/xfs/xfs_ag.h
index af3cfeb..f24b50b 100644
--- a/fs/xfs/xfs_ag.h
+++ b/fs/xfs/xfs_ag.h
@@ -91,6 +91,9 @@
 #define	XFS_AGF_BLOCK(mp)	XFS_HDR_BLOCK(mp, XFS_AGF_DADDR(mp))
 #define	XFS_BUF_TO_AGF(bp)	((xfs_agf_t *)XFS_BUF_PTR(bp))
 
+extern int xfs_read_agf(struct xfs_mount *mp, struct xfs_trans *tp,
+			xfs_agnumber_t agno, int flags, struct xfs_buf **bpp);
+
 /*
  * Size of the unlinked inode hash table in the agi.
  */