Only call rig_get_vfo in icom_set_vfo if get_vfo is enabled

src/rig.c

@@ -2629,6 +2629,8 @@ int HAMLIB_API rig_set_vfo(RIG *rig, vfo_t vfo)
 
     if (vfo == RIG_VFO_CURR) { RETURNFUNC(RIG_OK); }
 
+    if (rig->caps->get_vfo)
+    {
         retcode = rig_get_vfo(rig, &curr_vfo);
 
         if (retcode != RIG_OK)
@@ -2638,6 +2640,7 @@ int HAMLIB_API rig_set_vfo(RIG *rig, vfo_t vfo)
         }
 
         if (curr_vfo == vfo) { RETURNFUNC(RIG_OK); }
+    }
 
 #if 0 // removing this check 20210801 -- should be mapped already