arm64: dts: ti: k3: squelch warning about lack of #interrupt-cells

There are couple of places where INTA interrupt controller
lacks #interrupt-cells property. This leads to warnings of
the type:

arch/arm64/boot/dts/ti/k3-j721e-main.dtsi:147.51-156.5: Warning (interrupt_provider): /bus@100000/main-navss/interrupt-controller@33d00000: Missing #interrupt-cells in interrupt provider

when building TI device-tree files with W=2 warning level.
Fix these.
Signed-off-by: NSekhar Nori <nsekhar@ti.com>
Signed-off-by: NNishanth Menon <nm@ti.com>
Reviewed-by: NGrygorii Strashko <grygorii.strashko@ti.com>
Link: https://lore.kernel.org/r/20201127210128.9151-1-nsekhar@ti.com

arch/arm64/boot/dts/ti/k3-am65-main.dtsi

@@ -472,6 +472,7 @@
 			interrupt-controller;
 			interrupt-parent = <&intr_main_navss>;
 			msi-controller;
+			#interrupt-cells = <0>;
 			ti,sci = <&dmsc>;
 			ti,sci-dev-id = <179>;
 			ti,interrupt-ranges = <0 0 256>;

arch/arm64/boot/dts/ti/k3-j721e-main.dtsi

@@ -148,6 +148,7 @@
 			interrupt-controller;
 			interrupt-parent = <&main_navss_intr>;
 			msi-controller;
+			#interrupt-cells = <0>;
 			ti,sci = <&dmsc>;
 			ti,sci-dev-id = <209>;
 			ti,interrupt-ranges = <0 0 256>;