[actuators/asctec] disable the i2c hack for the general case

It can be activated for lisa/m boards with the flag:
USE_I2C_ACTUATORS_REBOOT_HACK

This issue should be handled at the i2c level (#71)

conf/airframes/examples/lisa_asctec.xml

@@ -196,6 +196,7 @@
       <define name="RADIO_MODE" value="RADIO_AUX2"/>
       <define name="RADIO_KILL_SWITCH" value="RADIO_GEAR"/>
       <define name="RADIO_CONTROL_SPEKTRUM_SIGNS" value="\{1,1,-1,1,-1,-1,-1,1,1,1,1,1\}"/>
+      <define name="USE_I2C_ACTUATORS_REBOOT_HACK"/>
     </target>
     <target name="sim" board="pc">
       <subsystem name="fdm"           type="jsbsim"/>

sw/airborne/subsystems/actuators/actuators_asctec.c

@@ -142,9 +142,11 @@ void actuators_asctec_set(bool_t motors_on) {
 #if defined ACTUATORS_START_DELAY && ! defined SITL
   if (!actuators_delay_done) {
     if (SysTimeTimer(actuators_delay_time) < USEC_OF_SEC(ACTUATORS_START_DELAY)) {
+#ifdef USE_I2C_ACTUATORS_REBOOT_HACK
       //Lisa-L with Asctech v2 motors only start after reflashing when a bus error was sensed on stm32-i2c.
       //multiple re-init solves the problem.
       i2c1_init();
+#endif
       return;
     }
     else actuators_delay_done = TRUE;