MIPS: Build fix - include <linux/smp.h> into all smp_processor_id() users.

Some of the were relying into smp.h being dragged in by another header
which of course is fragile.  <asm/cpu-info.h> uses smp_processor_id()
only in macros and including smp.h there leads to an include loop, so
don't change cpu-info.h.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
diff --git a/arch/mips/include/asm/irq.h b/arch/mips/include/asm/irq.h
index 4f1eed1..09b08d0 100644
--- a/arch/mips/include/asm/irq.h
+++ b/arch/mips/include/asm/irq.h
@@ -10,6 +10,7 @@
 #define _ASM_IRQ_H
 
 #include <linux/linkage.h>
+#include <linux/smp.h>
 
 #include <asm/mipsmtregs.h>