sched/headers: Remove duplicate #include <linux/sched/debug.h> line

Vito Caputo reported that the sched.h split-up series
introduced a duplicate #include <linux/sched/debug.h> line
in drivers/tty/vt/keyboard.c.

Remove it.
Reported-by: Vito Caputo <vcaputo@pengaru.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: Alan Cox <alan@linux.intel.com>
Cc: Greg Kroah-Hartman <gregkh@suse.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>

drivers/tty/vt/keyboard.c

@@ -28,7 +28,6 @@
 #include <linux/module.h>
 #include <linux/sched/signal.h>
 #include <linux/sched/debug.h>
-#include <linux/sched/debug.h>
 #include <linux/tty.h>
 #include <linux/tty_flip.h>
 #include <linux/mm.h>