btrfs: remove unused gfp mask parameter from release_extent_buffer callchain

It's unused since 0b32f4bbb423f02ac.

Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index ac132d9..2bc1ecf 100644
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -966,14 +966,8 @@
 {
 	if (PageWriteback(page) || PageDirty(page))
 		return 0;
-	/*
-	 * We need to mask out eg. __GFP_HIGHMEM and __GFP_DMA32 as we're doing
-	 * slab allocation from alloc_extent_state down the callchain where
-	 * it'd hit a BUG_ON as those flags are not allowed.
-	 */
-	gfp_flags &= ~GFP_SLAB_BUG_MASK;
 
-	return try_release_extent_buffer(page, gfp_flags);
+	return try_release_extent_buffer(page);
 }
 
 static void btree_invalidatepage(struct page *page, unsigned long offset)