sb/intel/i82371eb: Constify pci_devfn_t devices

Change-Id: I9056464b36cde89d2fe88ff27531e467297bed0b
Signed-off-by: Elyes Haouas <ehaouas@noos.fr>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/61986
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Felix Held <felix-coreboot@felixheld.de>
diff --git a/src/southbridge/intel/i82371eb/bootblock.c b/src/southbridge/intel/i82371eb/bootblock.c
index 05b2d2c..844106d 100644
--- a/src/southbridge/intel/i82371eb/bootblock.c
+++ b/src/southbridge/intel/i82371eb/bootblock.c
@@ -30,7 +30,6 @@
 void bootblock_early_southbridge_init(void)
 {
 	u16 reg16;
-	pci_devfn_t dev;
 
 	/*
 	 * Note: The Intel 82371AB/EB/MB ISA device can be on different
@@ -39,7 +38,7 @@
 	 * But scanning for the PCI IDs (instead of hardcoding
 	 * bus/device/function numbers) works on all boards.
 	 */
-	dev = pci_locate_device(PCI_ID(PCI_VENDOR_ID_INTEL,
+	const pci_devfn_t dev = pci_locate_device(PCI_ID(PCI_VENDOR_ID_INTEL,
 				       PCI_DEVICE_ID_INTEL_82371AB_ISA), 0);
 
 	/* Enable access to the whole ROM, disable ROM write access. */