ARM: dts: aspeed: quanta-q71: Enable p2a node

Enable the aspeed-p2a-ctrl node and configure with memory-region to
enable mmap access.
Signed-off-by: Patrick Venture <venture@google.com>
Signed-off-by: Joel Stanley <joel@jms.id.au>

arch/arm/boot/dts/aspeed-bmc-quanta-q71l.dts

@@ -112,6 +112,11 @@ &pinctrl {
 			&pinctrl_ddcclk_default &pinctrl_ddcdat_default>;
 };
 
+&p2a {
+	status = "okay";
+	memory-region = <&vga_memory>;
+};
+
 &ibt {
 	status = "okay";
 };