sched.c: Remove unused variable 'relative'

Getting rid of the p->children printout in show_task() left behind an
unused variable.
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

kernel/sched.c

@@ -4691,7 +4691,6 @@ static const char stat_nam[] = "RSDTtZX";
 
 static void show_task(struct task_struct *p)
 {
-	struct task_struct *relative;
 	unsigned long free = 0;
 	unsigned state;