sched/headers: Prepare to move kstack_end() from <linux/sched.h> to <linux/sched/task_stack.h>

But first update the usage sites with the new header dependency.

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>

arch/um/kernel/sysrq.c

@@ -12,6 +12,7 @@
 #include <linux/module.h>
 #include <linux/sched.h>
 #include <linux/sched/debug.h>
+#include <linux/sched/task_stack.h>
 
 #include <asm/sysrq.h>
 #include <asm/stacktrace.h>