arm/dt: 8974-v2: declare MDSS differences from 8974 v1 to v2

Some register offsets have changed between 8974 versions, these can be
handled by declaring them in device tree.

Change-Id: Id56c11114ec37549f278efc332eb19ca0143f7fe
Signed-off-by: Adrian Salido-Moreno <adrianm@codeaurora.org>
diff --git a/arch/arm/boot/dts/msm8974-mdss.dtsi b/arch/arm/boot/dts/msm8974-mdss.dtsi
index 079b882..b249883 100644
--- a/arch/arm/boot/dts/msm8974-mdss.dtsi
+++ b/arch/arm/boot/dts/msm8974-mdss.dtsi
@@ -11,7 +11,7 @@
  */
 
 / {
-	qcom,mdss_mdp@fd900000 {
+	mdss_mdp: qcom,mdss_mdp@fd900000 {
 		compatible = "qcom,mdss_mdp";
 		reg = <0xfd900000 0x22100>,
 			<0xfd924000 0x1000>;