Copter: do not spin motors during arming process

ArduCopter/motors.pde

@@ -110,9 +110,6 @@ static void init_arm_motors()
 
     // disable cpu failsafe because initialising everything takes a while
     failsafe_disable();
-    
-    motors.enable();
-    motors.output_unsafe();
 
 #if LOGGING_ENABLED == ENABLED
     // start dataflash
@@ -189,6 +186,9 @@ static void init_arm_motors()
         return;
     }
 
+    // enable output to motors
+    output_min();
+
     // finally actually arm the motors
     motors.armed(true);