ARM: SMP: pass an ipi number to smp_cross_call()

This allows us to use smp_cross_call() to trigger a number of different
software generated interrupts, rather than combining them all on one
SGI.  Recover the SGI number via do_IPI.

Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
diff --git a/arch/arm/kernel/entry-armv.S b/arch/arm/kernel/entry-armv.S
index c09e357..955cf5f 100644
--- a/arch/arm/kernel/entry-armv.S
+++ b/arch/arm/kernel/entry-armv.S
@@ -48,7 +48,7 @@
 	 */
 	ALT_SMP(test_for_ipi r0, r6, r5, lr)
 	ALT_UP_B(9997f)
-	movne	r0, sp
+	movne	r1, sp
 	adrne	lr, BSYM(1b)
 	bne	do_IPI