arm64: dts: renesas: r8a77990: Remove non-existing STBE region

R-Car E3 does not have the Stream Buffer for EtherAVB-IF (STBE).

Note that the RAVB driver does not use this region.

Fixes: 913a78b5 ("arm64: dts: renesas: r8a77990: Add EthernetAVB device nodes")
Signed-off-by: NGeert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: NSimon Horman <horms+renesas@verge.net.au>

arch/arm64/boot/dts/renesas/r8a77990.dtsi

@@ -213,7 +213,7 @@
 		avb: ethernet@e6800000 {
 			compatible = "renesas,etheravb-r8a77990",
 				     "renesas,etheravb-rcar-gen3";
-			reg = <0 0xe6800000 0 0x800>, <0 0xe6a00000 0 0x10000>;
+			reg = <0 0xe6800000 0 0x800>;
 			interrupts = <GIC_SPI 39 IRQ_TYPE_LEVEL_HIGH>,
 				     <GIC_SPI 40 IRQ_TYPE_LEVEL_HIGH>,
 				     <GIC_SPI 41 IRQ_TYPE_LEVEL_HIGH>,