small kernel/sched_debug.c cleanup - break up
multi-variable assignment.

no code changed:

   text    data     bss     dec     hex filename
   38869    3550      24   42443    a5cb sched.o.before
   38869    3550      24   42443    a5cb sched.o.after
Signed-off-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: NMike Galbraith <efault@gmx.de>
Reviewed-by: NThomas Gleixner <tglx@linutronix.de>