host/ble_hs: Add public API for getting the host eventq

- This is needed if we want to perform other operations on the host
eventq
- In our specific case we would like to perform all BLE comms related
  work on this eventq

nimble/host/include/host/ble_hs.h

@@ -445,7 +445,7 @@ void ble_hs_evq_set(struct ble_npl_eventq *evq);
  * host uses the default event queue and runs in the main task. This function
  * is useful if you want to find out what eventq the host is running on
  *
- * @param evq The event queue to use for the host work.
+ * @return evq The event queue thats being used for the host work.
  */
 struct ble_npl_eventq *ble_hs_evq_get(void);