metag: smp: don't set irq regs in do_IPI()

Since commit f6b30d32 (metag: kick: add missing irq_enter/exit to
kick_handler()), the main kick_handler() function deals with setting and
restoring the irq registers pointer. Therefore do_IPI() which is called
indirectly from kick_handler() doesn't need to do that itself any
longer. Therefore remove that code and do_IPI()'s pt_regs argument.
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: linux-metag@vger.kernel.org
Cc: Thomas Gleixner <tglx@linutronix.de>

arch/metag/kernel/smp.c

@@ -517,11 +517,10 @@ static DEFINE_SPINLOCK(stop_lock);
  *
  *  Bit 0 - Inter-processor function call
  */
-static int do_IPI(struct pt_regs *regs)
+static int do_IPI(void)
 {
 	unsigned int cpu = smp_processor_id();
 	struct ipi_data *ipi = &per_cpu(ipi_data, cpu);
-	struct pt_regs *old_regs = set_irq_regs(regs);
 	unsigned long msgs, nextmsg;
 	int handled = 0;
 
@@ -557,8 +556,6 @@ static int do_IPI(struct pt_regs *regs)
 		}
 	}
 
-	set_irq_regs(old_regs);
-
 	return handled;
 }
 
@@ -624,7 +621,7 @@ static void kick_raise_softirq(cpumask_t callmap, unsigned int irq)
 static TBIRES ipi_handler(TBIRES State, int SigNum, int Triggers,
 		   int Inst, PTBI pTBI, int *handled)
 {
-	*handled = do_IPI((struct pt_regs *)State.Sig.pCtx);
+	*handled = do_IPI();
 
 	return State;
 }