hw/mcu/da1469x: Make number of pins per port changeable
hw/mcu/da1469x: Make number of pins per port changeable

In custom hardware number of pins per port can differ from
usual 32 bits.
This changes pin accessing code to work with regular and
custom size of ports.

mlaz/mynewt-core,mlaz/mynewt-core,mlaz/mynewt-core,mlaz/mynewt-core,mlaz/mynewt-core