fix external interrupts, step dir now working

Firmware/MotorControl/axis.cpp

@@ -25,6 +25,10 @@ Axis::Axis(const AxisHardwareConfig_t& hw_config,
     motor_.axis_ = this;
 }
 
+static void step_cb_wrapper(void* ctx) {
+    reinterpret_cast<Axis*>(ctx)->step_cb();
+}
+
 // @brief Sets up all components of the axis,
 // such as gate driver and encoder hardware.
 void Axis::setup() {
@@ -56,10 +60,6 @@ bool Axis::wait_for_current_meas() {
     return osSignalWait(M_SIGNAL_PH_CURRENT_MEAS, PH_CURRENT_MEAS_TIMEOUT).status == osEventSignal;
 }
 
-static void step_cb_wrapper(void* ctx) {
-    reinterpret_cast<Axis*>(ctx)->step_cb();
-}
-
 // step/direction interface
 void Axis::step_cb() {
     if (enable_step_dir_) {