block: blkdev.h cleanup, move iocontext stuff to iocontext.h

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
diff --git a/kernel/exit.c b/kernel/exit.c
index 8f6185e..ceb2587 100644
--- a/kernel/exit.c
+++ b/kernel/exit.c
@@ -13,6 +13,7 @@
 #include <linux/personality.h>
 #include <linux/tty.h>
 #include <linux/mnt_namespace.h>
+#include <linux/iocontext.h>
 #include <linux/key.h>
 #include <linux/security.h>
 #include <linux/cpu.h>