x86: dts: link: Add board ID GPIOs

At present the board ID GPIOs are hard-coded. Move them to the device tree
so that we can use general SDRAM init code.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>

arch/x86/dts/chromebook_link.dts

@@ -74,6 +74,8 @@
 		northbridge@0,0 {
 			reg = <0x00000000 0 0 0 0>;
 			compatible = "intel,bd82x6x-northbridge";
+			board-id-gpios = <&gpio_b 9 0>, <&gpio_b 10 0>,
+					<&gpio_b 11 0>, <&gpio_a 10 0>;
 			u-boot,dm-pre-reloc;
 			spd {
 				compatible = "memory-spd";