AP_Periph: support mavlink based simulated devices in SITL periph

Tools/AP_Periph/wscript

@@ -81,6 +81,11 @@ def build(bld):
                      'AP_RobotisServo',
                      'AP_FETtecOneWire',
                      ]
+
+    if bld.env.BOARD == "sitl_periph_gps":
+        # sitl_periph_gps needs mavlink bindings for simulators
+        libraries.extend(['GCS_MAVLink'])
+
     bld.ap_stlib(
         name= 'AP_Periph_libs',
         dynamic_source='modules/DroneCAN/libcanard/dsdlc_generated/src/**.c',