ironlake: Fix compilation on x86_64

Use correct datasize to compile on x86_64.
Tested on Lenovo T410 with additional x86_64 patches.

Change-Id: I213b2b1c5de174b5c14b67d1b437d19c656d13fd
Signed-off-by: Patrick Rudolph <siro@das-labor.org>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/37371
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Angel Pons <th3fanbus@gmail.com>
diff --git a/src/southbridge/intel/ibexpeak/me.c b/src/southbridge/intel/ibexpeak/me.c
index 3477d8c..b355d9d 100644
--- a/src/southbridge/intel/ibexpeak/me.c
+++ b/src/southbridge/intel/ibexpeak/me.c
@@ -359,7 +359,7 @@
 	u32 reg32;
 	u16 reg16;
 
-	mei_base_address = (u32 *)
+	mei_base_address = (u32 *)(uintptr_t)
 		(pci_read_config32(PCH_ME_DEV, PCI_BASE_ADDRESS_0) & ~0xf);
 
 	/* S3 path will have hidden this device already */