sched/rt, ARC: Use CONFIG_PREEMPTION

CONFIG_PREEMPTION is selected by CONFIG_PREEMPT and by CONFIG_PREEMPT_RT.
Both PREEMPT and PREEMPT_RT require the same functionality which today
depends on CONFIG_PREEMPT.

Switch the entry code over to use CONFIG_PREEMPTION.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: linux-snps-arc@lists.infradead.org
Link: https://lore.kernel.org/r/20191015191821.11479-5-bigeasy@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>

arch/arc/kernel/entry.S

@@ -337,11 +337,11 @@ resume_user_mode_begin:
 resume_kernel_mode:
 
 	; Disable Interrupts from this point on
-	; CONFIG_PREEMPT: This is a must for preempt_schedule_irq()
-	; !CONFIG_PREEMPT: To ensure restore_regs is intr safe
+	; CONFIG_PREEMPTION: This is a must for preempt_schedule_irq()
+	; !CONFIG_PREEMPTION: To ensure restore_regs is intr safe
 	IRQ_DISABLE	r9
 
-#ifdef CONFIG_PREEMPT
+#ifdef CONFIG_PREEMPTION
 
 	; Can't preempt if preemption disabled
 	GET_CURR_THR_INFO_FROM_SP   r10