ARM: OMAP4+: Allow kexec on SMP variants

Kexec needs omap4_cpu_kill, otherwise kexec will produce on SMP:

kexec_load failed: Invalid argument

Acked-by: Santosh Shilimkar <ssantosh@kernel.org>
Tested-by: Keerthy <j-keerthy@ti.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
diff --git a/arch/arm/mach-omap2/common.h b/arch/arm/mach-omap2/common.h
index 0136405..deed42e 100644
--- a/arch/arm/mach-omap2/common.h
+++ b/arch/arm/mach-omap2/common.h
@@ -272,6 +272,7 @@
 extern u32 omap_read_auxcoreboot0(void);
 
 extern void omap4_cpu_die(unsigned int cpu);
+extern int omap4_cpu_kill(unsigned int cpu);
 
 extern const struct smp_operations omap4_smp_ops;