feat: Add support for SpaceMouse mod (6D input knob) (#1853)

Use `-DSPACEMOUSE=YES` CMake option to activate on Horus color targets.
Co-authored-by: Niel Horne (elecpower), Raphael Coeffic (raphaelcoeffic) and Peter Feerick (pfeerick).

radio/src/storage/yaml/yaml_datastructs_funcs.cpp

@@ -1855,6 +1855,7 @@ static const struct YamlIdStr enum_UartModes[] = {
   {  UART_MODE_CLI, "CLI"  },
   {  UART_MODE_GPS, "GPS"  },
   {  UART_MODE_DEBUG, "DEBUG"  },
+  {  UART_MODE_SPACEMOUSE, "SPACEMOUSE"  },
   {  0, NULL  }
 };