sched/headers: Prepare to remove the <linux/magic.h> include from <linux/sched/task_stack.h>

Update files that depend on the magic.h inclusion.

Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
diff --git a/drivers/virtio/virtio_balloon.c b/drivers/virtio/virtio_balloon.c
index 9d2738e..a610061 100644
--- a/drivers/virtio/virtio_balloon.c
+++ b/drivers/virtio/virtio_balloon.c
@@ -31,6 +31,7 @@
 #include <linux/wait.h>
 #include <linux/mm.h>
 #include <linux/mount.h>
+#include <linux/magic.h>
 
 /*
  * Balloon device works in 4K page units.  So each page is pointed to by