AP_NavEKF3: suppress ekf fail-to-set-origin if core disabled

libraries/AP_NavEKF3/AP_NavEKF3.cpp

@@ -1127,6 +1127,9 @@ bool NavEKF3::getOriginLLH(int8_t instance, struct Location &loc) const
 // Returns false if the filter has rejected the attempt to set the origin
 bool NavEKF3::setOriginLLH(const Location &loc)
 {
+    if (!core) {
+        return false;
+    }
     if (_fusionModeGPS != 3) {
         // we don't allow setting of the EKF origin unless we are
         // flying in non-GPS mode. This is to prevent accidental set
@@ -1134,9 +1137,6 @@ bool NavEKF3::setOriginLLH(const Location &loc)
         gcs().send_text(MAV_SEVERITY_WARNING, "EKF3 refusing set origin");
         return false;
     }
-    if (!core) {
-        return false;
-    }
     bool ret = false;
     for (uint8_t i=0; i<num_cores; i++) {
         ret |= core[i].setOriginLLH(loc);