arm64: dts: k3-j784s4-som-p0: Enable OSPI PHY mode

For achieving higher clocks speeds (greater than 25 MHz DDR) with OSPI,
OSPI PHY needs to be enabled and calibrate, add the necessary property
to enable PHY.

Signed-off-by: Vaishnav Achath <vaishnav.a@ti.com>

arch/arm/dts/k3-j784s4-evm.dts

@@ -703,6 +703,7 @@
 		cdns,tchsh-ns = <60>;
 		cdns,tslch-ns = <60>;
 		cdns,read-delay = <4>;
+		cdns,phy-mode;
 
 		partitions {
 			compatible = "fixed-partitions";