nilfs2: remove individual gfp constants for each metadata file

This gets rid of NILFS_CPFILE_GFP, NILFS_SUFILE_GFP, NILFS_DAT_GFP,
and NILFS_IFILE_GFP.  All of these constants refer to NILFS_MDT_GFP,
and can be removed.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
diff --git a/fs/nilfs2/mdt.h b/fs/nilfs2/mdt.h
index df683e0..4315997 100644
--- a/fs/nilfs2/mdt.h
+++ b/fs/nilfs2/mdt.h
@@ -74,8 +74,7 @@
 int nilfs_mdt_mark_block_dirty(struct inode *, unsigned long);
 int nilfs_mdt_fetch_dirty(struct inode *);
 
-struct inode *nilfs_mdt_new(struct the_nilfs *, struct super_block *, ino_t,
-			    gfp_t);
+struct inode *nilfs_mdt_new(struct the_nilfs *, struct super_block *, ino_t);
 struct inode *nilfs_mdt_new_common(struct the_nilfs *, struct super_block *,
 				   ino_t, gfp_t);
 void nilfs_mdt_destroy(struct inode *);