Keep the colleague's microbu-esp32c5 tree in this repository

obu-firmware builds against vanetza-idf from microbu-esp32c5/external, but
that tree was gitignored, so a clone of this repository could not build the
firmware it ships. It is now committed here as ordinary files in its own
folder, microbu-esp32c5/: the colleague's commit cf4b99f plus the V2X2MAP
bridge's signature verification (--trust) used on the bench. Nothing is
fetched from or pushed to the colleague's repository; this repository and
its remotes carry everything. The folder's own .gitignore keeps build output,
downloaded components and private key material out, as it did there; the
committed file set is identical to that repository's tracked files.

The ESP32-C5 is still flashed from obu-firmware/, which only takes
vanetza-idf from microbu-esp32c5/, so the two stay separate folders.
FLASHING.md says how to take a newer version of the colleague's tree (copy
it over the folder, rebuild, test, commit).

microbu-esp32c5/external/vanetza-idf/vanetza/security/v2/tests/check_region.hpp

@@ -0,0 +1,65 @@
+#ifndef CHECK_REGION_HPP_UFSV2RZ5
+#define CHECK_REGION_HPP_UFSV2RZ5
+
+#include <vanetza/security/v2/region.hpp>
+
+namespace vanetza
+{
+namespace security
+{
+namespace v2
+{
+
+/** \brief check two TwoDLocations
+ * \param expected the expected value
+ * \param actual the actual value
+ */
+void check(const TwoDLocation& expected, const TwoDLocation& actual);
+
+/** \brief check two ThreeDLocations
+ * \param expected the expected value
+ * \param actual the actual value
+ */
+void check(const ThreeDLocation&, const ThreeDLocation&);
+
+/** \brief check two CircularRegions
+ * \param expected the expected value
+ * \param actual the actual value
+ */
+void check(const CircularRegion& expected, const CircularRegion& actual);
+
+/** \brief check two RectangularRegions
+ * \param expected the expected value
+ * \param actual the actual value
+ */
+void check(const RectangularRegion& expected, const RectangularRegion& actual);
+
+/** \brief check two std::list<RectangularRegion>
+ * \param expected the expected list
+ * \param actual the actual value
+ */
+void check(std::list<RectangularRegion> expected, std::list<RectangularRegion> actual);
+
+/** \brief check two PolygonalRegions
+ * \param expected the expected value
+ * \param actual the actual value
+ */
+void check(PolygonalRegion expected, PolygonalRegion actual);
+
+/** \brief check two IdentifiedRegions
+ * \param expected the expected value
+ * \param actual the actual value
+ */
+void check(const IdentifiedRegion& expected, const IdentifiedRegion& actual);
+
+/** \brief check two GeographicRegion
+ * \param expected the expected value
+ * \param actual the actual value
+ */
+void check(const GeographicRegion& expected, const GeographicRegion& actual);
+
+} // namespace v2
+} // namespace security
+} // namespace vanetza
+
+#endif /* CHECK_REGION_HPP_UFSV2RZ5 */