MIPS: dts: lantiq: Remove bogus interrupt-parent; line

Specifying interrupt-parent without a value (in other words, as a bool)
doesn't really mean anything. Remove one such property in the Lantiq
Danube DT, at /sram@1f000000/eiu@101000.
Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

arch/mips/boot/dts/lantiq/danube.dtsi

@@ -40,7 +40,6 @@ sram@1f000000 {
 		eiu0: eiu@101000 {
 			#interrupt-cells = <1>;
 			interrupt-controller;
-			interrupt-parent;
 			compatible = "lantiq,eiu-xway";
 			reg = <0x101000 0x1000>;
 		};