device/pci: Replace add with bitwise-or

Change-Id: I9fbefac3bef7425d6f5ea1bcc01eb21485315c36
Signed-off-by: Kyösti Mälkki <kyosti.malkki@gmail.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/35517
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Nico Huber <nico.h@gmx.de>
Reviewed-by: Michael Niewöhner
Reviewed-by: Angel Pons <th3fanbus@gmail.com>
diff --git a/src/device/pci_device.c b/src/device/pci_device.c
index 7ecb652..c043dd6 100644
--- a/src/device/pci_device.c
+++ b/src/device/pci_device.c
@@ -626,7 +626,7 @@
 		dev->command |= PCI_COMMAND_IO;
 	ctrl = pci_read_config16(dev, PCI_BRIDGE_CONTROL);
 	ctrl |= dev->link_list->bridge_ctrl;
-	ctrl |= (PCI_BRIDGE_CTL_PARITY + PCI_BRIDGE_CTL_SERR); /* Error check. */
+	ctrl |= (PCI_BRIDGE_CTL_PARITY | PCI_BRIDGE_CTL_SERR); /* Error check. */
 	printk(BIOS_DEBUG, "%s bridge ctrl <- %04x\n", dev_path(dev), ctrl);
 	pci_write_config16(dev, PCI_BRIDGE_CONTROL, ctrl);