nrf/boards/arduino_primo: Add missing hal_rng config used by random mod.
#define HAL_TWI_MODULE_ENABLED
#define HAL_ADCE_MODULE_ENABLED
#define HAL_TEMP_MODULE_ENABLED
+#define HAL_RNG_MODULE_ENABLED
// #define HAL_UARTE_MODULE_ENABLED
// #define HAL_SPIE_MODULE_ENABLED
// #define HAL_TWIE_MODULE_ENABLED
