ver: print PX4_BOARD_LABEL for 'ver all'

src/lib/version/CMakeLists.txt

@@ -79,6 +79,7 @@ add_library(version version.c)
 target_compile_definitions(version
 	PUBLIC
 		PX4_BOARD_NAME="${PX4_BOARD_NAME}"
+		PX4_BOARD_LABEL="${PX4_BOARD_LABEL}"
 	PRIVATE
 		BUILD_URI=${BUILD_URI}
 	)

src/lib/version/version.h

@@ -56,6 +56,14 @@ static inline const char *px4_board_name(void)
 	return PX4_BOARD_NAME;
 }
 
+/**
+ * get the board build target variant
+ */
+static inline const char *px4_board_target_label(void)
+{
+	return PX4_BOARD_LABEL;
+}
+
 /**
  * get the board sub type
  */