arm64: dts: qcom: msm8916: rename WCNSS child name to bluetooth

The "bluetooth" is more popular and more descriptive than "bt", for a
Bluetooth device.  The WCNSS DT schema will expect such naming.
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Link: https://lore.kernel.org/r/20220405065752.27389-2-krzysztof.kozlowski@linaro.org

arch/arm64/boot/dts/qcom/msm8916.dtsi

@@ -1788,7 +1788,7 @@ wcnss_ctrl: wcnss {
 
 					qcom,mmio = <&pronto>;
 
-					bt {
+					bluetooth {
 						compatible = "qcom,wcnss-bt";
 					};