AP_AHRS_NavEKF: use millis/micros/panic functions

libraries/AP_AHRS/AP_AHRS_NavEKF.cpp

@@ -93,9 +93,9 @@ void AP_AHRS_NavEKF::update_EKF1(void)
     if (!ekf1_started) {
         // wait 1 second for DCM to output a valid tilt error estimate
         if (start_time_ms == 0) {
-            start_time_ms = hal.scheduler->millis();
+            start_time_ms = AP_HAL::millis();
         }
-        if (hal.scheduler->millis() - start_time_ms > startup_delay_ms) {
+        if (AP_HAL::millis() - start_time_ms > startup_delay_ms) {
             ekf1_started = EKF1.InitialiseFilterDynamic();
         }
     }
@@ -163,9 +163,9 @@ void AP_AHRS_NavEKF::update_EKF2(void)
     if (!ekf2_started) {
         // wait 1 second for DCM to output a valid tilt error estimate
         if (start_time_ms == 0) {
-            start_time_ms = hal.scheduler->millis();
+            start_time_ms = AP_HAL::millis();
         }
-        if (hal.scheduler->millis() - start_time_ms > startup_delay_ms) {
+        if (AP_HAL::millis() - start_time_ms > startup_delay_ms) {
             ekf2_started = EKF2.InitialiseFilter();
         }
     }
@@ -633,11 +633,11 @@ bool AP_AHRS_NavEKF::initialised(void) const
     case 1:
     default:
         // initialisation complete 10sec after ekf has started
-        return (ekf1_started && (hal.scheduler->millis() - start_time_ms > AP_AHRS_NAVEKF_SETTLE_TIME_MS));
+        return (ekf1_started && (AP_HAL::millis() - start_time_ms > AP_AHRS_NAVEKF_SETTLE_TIME_MS));
 
     case 2:
         // initialisation complete 10sec after ekf has started
-        return (ekf2_started && (hal.scheduler->millis() - start_time_ms > AP_AHRS_NAVEKF_SETTLE_TIME_MS));
+        return (ekf2_started && (AP_HAL::millis() - start_time_ms > AP_AHRS_NAVEKF_SETTLE_TIME_MS));
     }
 };