nrf/bluetooth: Improve advertisment behavior for nrf52 targets.

This patch makes sure that advertisment data is located in
persistent static RAM memory throughout the advertisment.

Also, setting m_adv_handle to predifined
BLE_GAP_ADV_SET_HANDLE_NOT_SET value to indicate first time
usage of the handle. Upon first advertisment configuration
this will be populated with a handle value returned by the
stack (s132/s140).

ports/nrf/drivers/bluetooth/ble_drv.c

@@ -109,7 +109,7 @@ static mp_obj_t mp_gattc_char_data_observer;
 #define BLE_GAP_ADV_MAX_SIZE 31
 #define BLE_DRV_CONN_CONFIG_TAG 1
 
-static uint8_t m_adv_handle;
+static uint8_t m_adv_handle = BLE_GAP_ADV_SET_HANDLE_NOT_SET;
 static uint8_t m_scan_buffer[BLE_GAP_SCAN_BUFFER_MIN];
 
 nrf_nvic_state_t nrf_nvic_state = {0};
@@ -407,7 +407,7 @@ bool ble_drv_advertise_data(ubluepy_advertise_data_t * p_adv_params) {
 
     uint8_t byte_pos = 0;
 
-    uint8_t adv_data[BLE_GAP_ADV_MAX_SIZE];
+    static uint8_t adv_data[BLE_GAP_ADV_MAX_SIZE];
 
     if (p_adv_params->device_name_len > 0) {
         ble_gap_conn_sec_mode_t sec_mode;