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 <[e-mail]>
Cc: Greg Kroah-Hartman <[e-mail]>
Cc: Jiri Slaby <[e-mail]>
Cc: Alan Cox <[e-mail]>
Cc: Greg Kroah-Hartman <[e-mail]>
Cc: Linus Torvalds <[e-mail]>
Cc: [e-mail]
Signed-off-by: Ingo Molnar <[e-mail]>

drivers/tty/vt/keyboard.c

···
 #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>