device: DDR3 generic code 64bit fix

Signed-off-by: Stefan Reinauer <stefan.reinauer@coreboot.org>

Change-Id: I5ff309948c36289eedeb8a18030cdd2b4c337690
Reviewed-on: http://review.coreboot.org/10595
Tested-by: build bot (Jenkins)
Reviewed-by: Marc Jones <marc.jones@se-eng.com>

src/include/device/dram/ddr3.h

@@ -186,7 +186,7 @@ void dram_print_spd_ddr3(const dimm_attr * dimm);
  *
  * Should be useful when doing an MRS to the DIMM
  */
-static inline u32 volatile_read(volatile u32 addr)
+static inline u32 volatile_read(volatile uintptr_t addr)
 {
 	volatile u32 result;
 	result = *(volatile u32 *)addr;