powerpc/mpic_msgr: Add missing includes

Add several #includes that mpic_msgr relies on being pulled implicitly,
which only happens on certain configs.

Signed-off-by: Scott Wood <scottwood@freescale.com>
Cc: Meador Inge <meador_inge@mentor.com>
Cc: Jia Hongtao <B38951@freescale.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

arch/powerpc/include/asm/mpic_msgr.h

@@ -14,6 +14,7 @@
 #include <linux/types.h>
 #include <linux/spinlock.h>
 #include <asm/smp.h>
+#include <asm/io.h>
 
 struct mpic_msgr {
 	u32 __iomem *base;

arch/powerpc/sysdev/mpic_msgr.c

@@ -14,6 +14,9 @@
 #include <linux/list.h>
 #include <linux/of_platform.h>
 #include <linux/errno.h>
+#include <linux/err.h>
+#include <linux/export.h>
+#include <linux/slab.h>
 #include <asm/prom.h>
 #include <asm/hw_irq.h>
 #include <asm/ppc-pci.h>