sched/headers: Prepare for the removal of <asm/ptrace.h> from <linux/sched.h>

Fix up missing #includes in other places that rely on sched.h doing that for them.

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/alpha/math-emu/math.c

@@ -2,6 +2,7 @@
 #include <linux/types.h>
 #include <linux/kernel.h>
 #include <linux/sched.h>
+#include <asm/ptrace.h>
 
 #include <linux/uaccess.h>