iomap: start moving code to fs/iomap/

Create the build infrastructure we need to start migrating iomap code to
fs/iomap/ from fs/iomap.c.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>

Author: djwong

MAINTAINERS

@@ -8362,6 +8362,7 @@ L:	linux-fsdevel@vger.kernel.org
 T:	git git://git.kernel.org/pub/scm/fs/xfs/xfs-linux.git
 S:	Supported
 F:	fs/iomap.c
+F:	fs/iomap/
 F:	include/linux/iomap.h
 
 IOMMU DRIVERS

fs/Makefile

@@ -53,6 +53,7 @@ obj-$(CONFIG_SYSCTL)		+= drop_caches.o
 
 obj-$(CONFIG_FHANDLE)		+= fhandle.o
 obj-$(CONFIG_FS_IOMAP)		+= iomap.o
+obj-y				+= iomap/
 
 obj-y				+= quota/
 

fs/iomap/Makefile

@@ -0,0 +1,5 @@
+# SPDX-License-Identifier: GPL-2.0-or-newer
+#
+# Copyright (c) 2019 Oracle.
+# All Rights Reserved.
+#