ARM: dts: keystone-k2hk: Add MSM RAM node

Add the RAM managed by the Multicore Shared Memory Controller (MSMC)
as a mmio-sram node. The 66AK2H SoCs have 6 MB of such memory. Any
specific MSM memory range needed by a software module ought to be
reserved using an appropriate child node.
Signed-off-by: Suman Anna <s-anna@ti.com>
Signed-off-by: Santosh Shilimkar <ssantosh@kernel.org>

arch/arm/boot/dts/keystone-k2hk.dtsi

@@ -46,6 +46,14 @@ cpu@3 {
 	soc {
 		/include/ "keystone-k2hk-clocks.dtsi"
 
+		msm_ram: msmram@0c000000 {
+			compatible = "mmio-sram";
+			reg = <0x0c000000 0x600000>;
+			ranges = <0x0 0x0c000000 0x600000>;
+			#address-cells = <1>;
+			#size-cells = <1>;
+		};
+
 		dspgpio0: keystone_dsp_gpio@02620240 {
 			compatible = "ti,keystone-dsp-gpio";
 			gpio-controller;