arm64: dts: qcom: sm8350: align MMC node names with DT schema

The bindings expect "mmc" for MMC/SDHCI nodes:

  sm8350-sony-xperia-sagami-pdx214.dtb: sdhci@8804000: $nodename:0: 'sdhci@8804000' does not match '^mmc(@.*)?$'
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/20221223161835.112079-4-krzysztof.kozlowski@linaro.org

arch/arm64/boot/dts/qcom/sm8350.dtsi

@@ -2378,7 +2378,7 @@ compute-cb@8 {
 			};
 		};
 
-		sdhc_2: sdhci@8804000 {
+		sdhc_2: mmc@8804000 {
 			compatible = "qcom,sm8350-sdhci", "qcom,sdhci-msm-v5";
 			reg = <0 0x08804000 0 0x1000>;