x86: Change MMIO addr in readN(addr)/writeN(addr, val) to pointer

On x86, change the type of the address parameter in
read8()/read16/read32()/write8()/write16()/write32() to be a
pointer, instead of unsigned long.

Change-Id: Ic26dd8a72d82828b69be3c04944710681b7bd330
Signed-off-by: Kevin Paul Herbert <kph@meraki.net>
Signed-off-by: Alexandru Gagniuc <mr.nuke.me@gmail.com>
Reviewed-on: http://review.coreboot.org/7784
Tested-by: build bot (Jenkins)
diff --git a/src/mainboard/kontron/986lcd-m/mptable.c b/src/mainboard/kontron/986lcd-m/mptable.c
index 03f7370..2df0a44 100644
--- a/src/mainboard/kontron/986lcd-m/mptable.c
+++ b/src/mainboard/kontron/986lcd-m/mptable.c
@@ -56,7 +56,7 @@
 
 	/* I/O APICs:	APIC ID	Version	State		Address */
 	ioapic_id = 2;
-	smp_write_ioapic(mc, ioapic_id, 0x20, IO_APIC_ADDR);
+	smp_write_ioapic(mc, ioapic_id, 0x20, VIO_APIC_VADDR);
 
 	/* Legacy Interrupts */
 	mptable_add_isa_interrupts(mc, isa_bus, ioapic_id, 0);