arm64: dts: qcom: sc8180x-pmics: align LPG node name with dtschema

Bindings expect the LPG node name to be "pwm":

  sc8180x-lenovo-flex-5g.dtb: pmic@5: 'lpg' does not match any of the regexes:

Fixes: d3302290 ("arm64: dts: qcom: sc8180x: Add pmics")
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Reviewed-by: Vinod Koul <vkoul@kernel.org>
Reviewed-by: Konrad Dybcio <konrad.dybcio@linaro.org>
Link: https://lore.kernel.org/r/20230720083500.73554-4-krzysztof.kozlowski@linaro.org


Signed-off-by: Bjorn Andersson <andersson@kernel.org>