sendfile: remove .sendfile from filesystems that use generic_file_sendfile()

They can use generic_file_splice_read() instead. Since sys_sendfile() now
prefers that, there should be no change in behaviour.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
diff --git a/fs/udf/file.c b/fs/udf/file.c
index 51b5764..df070be 100644
--- a/fs/udf/file.c
+++ b/fs/udf/file.c
@@ -261,7 +261,7 @@
 	.aio_write		= udf_file_aio_write,
 	.release		= udf_release_file,
 	.fsync			= udf_fsync_file,
-	.sendfile		= generic_file_sendfile,
+	.splice_read		= generic_file_splice_read,
 };
 
 const struct inode_operations udf_file_inode_operations = {