fs: move the fiemap definitions out of fs.h

No need to pull the fiemap definitions into almost every file in the
kernel build.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Ritesh Harjani <riteshh@linux.ibm.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Link: https://lore.kernel.org/r/20200523073016.2944131-5-hch@lst.de
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

fs/overlayfs/inode.c

@@ -10,6 +10,7 @@
 #include <linux/xattr.h>
 #include <linux/posix_acl.h>
 #include <linux/ratelimit.h>
+#include <linux/fiemap.h>
 #include "overlayfs.h"