efi: Support a 64-bit frame buffer address

The current vesa structure only provides a 32-bit value for the frame
buffer. Many modern machines use an address outside the range.

It is still useful to have this common struct, but add a separate
frame-buffer address as well.

Add a comment for vesa_setup_video_priv() while we are here.

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/drivers/video/coreboot.c b/drivers/video/coreboot.c
index d2d87c7..c586475 100644
--- a/drivers/video/coreboot.c
+++ b/drivers/video/coreboot.c
@@ -57,7 +57,7 @@
 		goto err;
 	}
 
-	ret = vesa_setup_video_priv(vesa, uc_priv, plat);
+	ret = vesa_setup_video_priv(vesa, vesa->phys_base_ptr, uc_priv, plat);
 	if (ret) {
 		ret = log_msg_ret("setup", ret);
 		goto err;