modules: hal_nordic: inject CONFIG_NFCT_PINS_AS_GPIOS

If the users configures this option in devicetree, ie,

```
&uicr {
    nfct-pins-as-gpios;
};
```

CMake will inject the HAL-specific CONFIG_NFCT_PINS_AS_GPIOS definition,
so that the necessary operations are performed during system init.

Signed-off-by: Gerard Marull-Paretas <gerard@teslabs.com>