arm64: dts: qcom: msm8996: align bus node names with DT schema

The node names should be generic and the bindings expect "bus" for
simple-bus nodes:

  msm8996-mtp.dtb: agnoc@0: $nodename:0: 'agnoc@0' does not match '^bus(@[0-9a-f]+)?$'
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Reviewed-by: Konrad Dybcio <konrad.dybcio@linaro.org>
Signed-off-by: Bjorn Andersson <andersson@kernel.org>
Link: https://lore.kernel.org/r/20221224154255.43499-1-krzysztof.kozlowski@linaro.org

arch/arm64/boot/dts/qcom/msm8996.dtsi

@@ -1818,7 +1818,7 @@ spmi_bus: spmi@400f000 {
 			#interrupt-cells = <4>;
 		};
 
-		agnoc@0 {
+		bus@0 {
 			power-domains = <&gcc AGGRE0_NOC_GDSC>;
 			compatible = "simple-pm-bus";
 			#address-cells = <1>;