ARM: dts: st: stm32mp157c-emstamp: correct regulator-active-discharge

The "regulator-active-discharge" property is uint32, not boolean:

  stm32mp157c-emsbc-argon.dtb: stpmic@33: regulators:pwr_sw1:regulator-active-discharge: True is not of type 'array'

Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Alexandre Torgue <alexandre.torgue@foss.st.com>