sb/common/smihandler: Fix 16-bit read/write to PCI_COMMAND register

Change-Id: Ib403f5a231f86bdc60b956e72a4ae631aa6a3899
Signed-off-by: Elyes HAOUAS <ehaouas@noos.fr>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/40742
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Paul Menzel <paulepanter@users.sourceforge.net>
Reviewed-by: Nico Huber <nico.h@gmx.de>
diff --git a/src/southbridge/intel/common/smihandler.c b/src/southbridge/intel/common/smihandler.c
index 7d4066d..7b27ce0 100644
--- a/src/southbridge/intel/common/smihandler.c
+++ b/src/southbridge/intel/common/smihandler.c
@@ -61,7 +61,7 @@
 
 	for (slot = 0; slot < 0x20; slot++) {
 		for (func = 0; func < 8; func++) {
-			u32 reg32;
+			u16 reg16;
 			pci_devfn_t dev = PCI_DEV(bus, slot, func);
 
 			val = pci_read_config32(dev, PCI_VENDOR_ID);
@@ -71,9 +71,9 @@
 				continue;
 
 			/* Disable Bus Mastering for this one device */
-			reg32 = pci_read_config32(dev, PCI_COMMAND);
-			reg32 &= ~PCI_COMMAND_MASTER;
-			pci_write_config32(dev, PCI_COMMAND, reg32);
+			reg16 = pci_read_config16(dev, PCI_COMMAND);
+			reg16 &= ~PCI_COMMAND_MASTER;
+			pci_write_config16(dev, PCI_COMMAND, reg16);
 
 			/* If this is a bridge, then follow it. */
 			hdr = pci_read_config8(dev, PCI_HEADER_TYPE);