pci: Disable expansion ROM address decoding when signature check fails

We should not leave the expansion ROM address window open when there
is not a valid ROM.

Suggested-by: Matt Porter <mporter@konsulko.com>
Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Tested-by: Simon Glass <sjg@chromium.org>
Acked-by: Simon Glass <sjg@chromium.org>

drivers/pci/pci_rom.c

@@ -104,6 +104,10 @@ static int pci_rom_probe(pci_dev_t dev, uint class,
 	if (le16_to_cpu(rom_header->signature) != PCI_ROM_HDR) {
 		printf("Incorrect expansion ROM header signature %04x\n",
 		       le16_to_cpu(rom_header->signature));
+#ifndef CONFIG_VGA_BIOS_ADDR
+		/* Disable expansion ROM address decoding */
+		pci_write_config_dword(dev, PCI_ROM_ADDRESS, rom_address);
+#endif
 		return -EINVAL;
 	}