[ARM] Allow arch/arm/kernel/bios32.c to build for iop310

bios32.c uses outb(), and therefore should have asm/io.h included.

arch/arm/kernel/bios32.c

@@ -12,6 +12,7 @@
 #include <linux/init.h>
 
 #include <asm/page.h> /* for BUG() */
+#include <asm/io.h>
 #include <asm/irq.h>
 #include <asm/mach-types.h>
 #include <asm/mach/pci.h>