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FLASHING.md says how to take a newer version of the colleague's tree (copy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/geonet/mib.cpp

@@ -0,0 +1,66 @@
+#include "mib.hpp"
+#include <boost/units/systems/si/prefixes.hpp>
+
+namespace vanetza
+{
+namespace geonet
+{
+
+using namespace vanetza::units::si;
+using vanetza::units::degrees;
+using boost::units::si::kilo;
+using boost::units::si::milli;
+
+const auto milliseconds = milli * seconds;
+
+ManagementInformationBase::ManagementInformationBase() :
+    itsGnLocalAddrConfMethod(AddrConfMethod::Managed),
+    itsGnProtocolVersion(1),
+    itsGnIsMobile(true),
+    itsGnIfType(InterfaceType::ITS_G5),
+    itsGnMinimumUpdateFrequencyEPV(1.0 / (1000.0 * milliseconds)),
+    itsGnPaiInterval(80 * meters),
+    itsGnMaxSduSize(1398),
+    itsGnMaxGeoNetworkingHeaderSize(88),
+    itsGnLifetimeLocTE(20 * seconds),
+    itsGnSecurity(false),
+    itsGnSnDecapResultHandling(SecurityDecapHandling::Strict),
+    itsGnLocationServiceMaxRetrans(10),
+    itsGnLocationServiceRetransmitTimer(1 * seconds),
+    itsGnLocationServicePacketBufferSize(1024),
+    itsGnBeaconServiceRetransmitTimer(3 * seconds),
+    itsGnBeaconServiceMaxJitter(itsGnBeaconServiceRetransmitTimer / 4.0),
+    itsGnDefaultHopLimit(10),
+    itsGnDPLLength(8),
+    itsGnMaxPacketLifetime(Lifetime::Base::Hundred_Seconds, 6),
+    itsGnDefaultPacketLifetime(Lifetime::Base::Ten_Seconds, 6),
+    itsGnMaxPacketDataRate(100),
+    itsGnMaxPacketDataRateEmaBeta(0.9),
+    itsGnMaxGeoAreaSize(10 * kilo * kilo * square_meters),
+    itsGnMinPacketRepetitionInterval(100 * milliseconds),
+    itsGnNonAreaForwardingAlgorithm(UnicastForwarding::Greedy),
+    itsGnAreaForwardingAlgorithm(BroadcastForwarding::CBF),
+    itsGnCbfMinTime(1 * milliseconds),
+    itsGnCbfMaxTime(100 * milliseconds),
+    itsGnDefaultMaxCommunicationRange(1000 * meters),
+    itsGnBroadcastCBFDefSectorAngle(30 * degrees),
+    itsGnUcForwardingPacketBufferSize(256),
+    itsGnBcForwardingPacketBufferSize(1024),
+    itsGnCbfPacketBufferSize(256),
+    itsGnDefaultTrafficClass(false, false, 0),
+    vanetzaDefaultSeed(0xc0114c2c),
+    vanetzaCbfMaxCounter(1),
+    vanetzaDeferInitialBeacon(Clock::duration::zero()),
+    vanetzaDisableBeaconing(false),
+    vanetzaMultiHopDuplicateAddressDetection(false),
+    vanetzaFadingCbfCounter(false),
+    vanetzaFadingCbfCounterLifetime(4.0 * itsGnCbfMaxTime),
+    vanetzaNeighbourFlagExpiry(Clock::duration::zero()),
+    vanetzaGbcMemoryCapacity(0),
+    vanetzaGbcPassUpOutsideDestination(false)
+{
+}
+
+} // namespace geonet
+} // namespace vanetza
+