[M252KG] Force enum PinName to 32-bit
[M252KG] Force enum PinName to 32-bit

NU_PINNAME_BIND(...) requires enum PinName to be 32-bit to encode module
binding information in it.

mbedmicro/mbed,andcor02/mbed-os,andcor02/mbed-os,andcor02/mbed-os,mbedmicro/mbed,andcor02/mbed-os,mbedmicro/mbed,mbedmicro/mbed,kjbracey-arm/mbed,andcor02/mbed-os,kjbracey-arm/mbed,kjbracey-arm/mbed,kjbracey-arm/mbed,andcor02/mbed-os,mbedmicro/mbed