drivers/nrf52: do not set IRQ prio for RIOT

RIOT does not allow for nested interrupts and initializes all IRQs
to the same priority during system initialization. Assigning
different priorities in the driver leads to system crashes.

nimble/drivers/nrf52/src/ble_hw.c

@@ -319,7 +319,9 @@ ble_hw_rng_init(ble_rng_isr_cb_t cb, int bias)
 
     /* If we were passed a function pointer we need to enable the interrupt */
     if (cb != NULL) {
+#ifndef RIOT_VERSION
         NVIC_SetPriority(RNG_IRQn, (1 << __NVIC_PRIO_BITS) - 1);
+#endif
 #if MYNEWT
         NVIC_SetVector(RNG_IRQn, (uint32_t)ble_rng_isr);
 #else

nimble/drivers/nrf52/src/ble_phy.c

@@ -1440,7 +1440,9 @@ ble_phy_init(void)
     NRF_PPI->CH[5].TEP = (uint32_t)&(NRF_RADIO->TASKS_DISABLE);
 
     /* Set isr in vector table and enable interrupt */
+#ifndef RIOT_VERSION
     NVIC_SetPriority(RADIO_IRQn, 0);
+#endif
 #if MYNEWT
     NVIC_SetVector(RADIO_IRQn, (uint32_t)ble_phy_isr);
 #else