ARM: iop32x: use __iomem pointers for MMIO

ARM is moving to stricter checks on readl/write functions,
so we need to use the correct types everywhere.

Cc: Imre Kaloz <kaloz@openwrt.org>
Cc: Krzysztof Halasa <khc@pm.waw.pl>
Cc: Lennert Buytenhek <buytenh@wantstofly.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
diff --git a/arch/arm/mach-iop32x/glantank.c b/arch/arm/mach-iop32x/glantank.c
index c15a100..02e20c3 100644
--- a/arch/arm/mach-iop32x/glantank.c
+++ b/arch/arm/mach-iop32x/glantank.c
@@ -183,7 +183,7 @@
 
 static void glantank_power_off(void)
 {
-	__raw_writeb(0x01, 0xfe8d0004);
+	__raw_writeb(0x01, IOMEM(0xfe8d0004));
 
 	while (1)
 		;