md: move lots of #include lines out of .h files and into .c

This makes the includes more explicit, and is preparation for moving
md_k.h to drivers/md/md.h

Remove include/raid/md.h as its only remaining use was to #include
other files.

Signed-off-by: NeilBrown <neilb@suse.de>
diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c
index f75698b..816157e 100644
--- a/drivers/md/raid5.c
+++ b/drivers/md/raid5.c
@@ -43,8 +43,12 @@
  * miss any bits.
  */
 
+#include <linux/blkdev.h>
+#include <linux/raid/md_k.h>
 #include <linux/kthread.h>
 #include <linux/async_tx.h>
+#include <linux/seq_file.h>
+#include "raid5.h"
 #include "raid6.h"
 #include "bitmap.h"
 
@@ -1467,7 +1471,7 @@
 
 static void compute_parity6(struct stripe_head *sh, int method)
 {
-	raid6_conf_t *conf = sh->raid_conf;
+	raid5_conf_t *conf = sh->raid_conf;
 	int i, pd_idx = sh->pd_idx, qd_idx, d0_idx, disks = sh->disks, count;
 	struct bio *chosen;
 	/**** FIX THIS: This could be very bad if disks is close to 256 ****/
@@ -2795,7 +2799,7 @@
 
 static bool handle_stripe6(struct stripe_head *sh, struct page *tmp_page)
 {
-	raid6_conf_t *conf = sh->raid_conf;
+	raid5_conf_t *conf = sh->raid_conf;
 	int disks = sh->disks;
 	struct bio *return_bi = NULL;
 	int i, pd_idx = sh->pd_idx;