dts: qcom: adjust pmic gpio to use upstream bindings

Use the upstream gpio-ranges property instead of gpio-count, and drop
the bank-name property for Qualcomm boards.

Reviewed-by: Neil Armstrong <neil.armstrong@linaro.org>
Reviewed-by: Sumit Garg <sumit.garg@linaro.org>
Tested-by: Sumit Garg <sumit.garg@linaro.org>
Signed-off-by: Caleb Connolly <caleb.connolly@linaro.org>