pci: Mask the ROM address in case it is already enabled

In some cases the video ROM may have been enabled previously, such as by
a previous firmware stage. Use the correct address in that case.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
diff --git a/drivers/pci/pci_rom.c b/drivers/pci/pci_rom.c
index 503feb1..438583a 100644
--- a/drivers/pci/pci_rom.c
+++ b/drivers/pci/pci_rom.c
@@ -93,6 +93,7 @@
 		debug("%s: rom_address=%x\n", __func__, rom_address);
 		return -ENOENT;
 	}
+	rom_address &= PCI_ROM_ADDRESS_MASK;
 
 	/* Enable expansion ROM address decoding. */
 	dm_pci_write_config32(dev, PCI_ROM_ADDRESS,