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FLASHING.md says how to take a newer version of the colleague's tree (copy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/asn1/patches/iso/circular-dependencies.patch

@@ -0,0 +1,75 @@
+diff --git a/vanetza/asn1/its/ConnectionManeuverAssist-addGrpC.c b/vanetza/asn1/its/ConnectionManeuverAssist-addGrpC.c
+index 479097e44..4067a8953 100644
+--- a/vanetza/asn1/its/ConnectionManeuverAssist-addGrpC.c
++++ b/vanetza/asn1/its/ConnectionManeuverAssist-addGrpC.c
+@@ -6,6 +6,7 @@
+  */
+ 
+ #include "ConnectionManeuverAssist-addGrpC.h"
++#include "ItsStationPositionList.h"
+ 
+ asn_TYPE_member_t asn_MBR_ConnectionManeuverAssist_addGrpC_1[] = {
+ 	{ ATF_POINTER, 1, offsetof(struct ConnectionManeuverAssist_addGrpC, itsStationPosition),
+diff --git a/vanetza/asn1/its/ConnectionManeuverAssist-addGrpC.h b/vanetza/asn1/its/ConnectionManeuverAssist-addGrpC.h
+index 5fab8e140..705cbd324 100644
+--- a/vanetza/asn1/its/ConnectionManeuverAssist-addGrpC.h
++++ b/vanetza/asn1/its/ConnectionManeuverAssist-addGrpC.h
+@@ -43,7 +43,7 @@ extern asn_TYPE_member_t asn_MBR_ConnectionManeuverAssist_addGrpC_1[1];
+ #endif
+ 
+ /* Referred external types */
+-#include "ItsStationPositionList.h"
++/* #include "ItsStationPositionList.h" */
+ 
+ #endif	/* _ConnectionManeuverAssist_addGrpC_H_ */
+ #include "asn_internal.h"
+diff --git a/vanetza/asn1/its/MapData-addGrpC.c b/vanetza/asn1/its/MapData-addGrpC.c
+index 771d73165..b5481881f 100644
+--- a/vanetza/asn1/its/MapData-addGrpC.c
++++ b/vanetza/asn1/its/MapData-addGrpC.c
+@@ -6,6 +6,7 @@
+  */
+ 
+ #include "MapData-addGrpC.h"
++#include "SignalHeadLocationList.h"
+ 
+ asn_TYPE_member_t asn_MBR_MapData_addGrpC_1[] = {
+ 	{ ATF_POINTER, 1, offsetof(struct MapData_addGrpC, signalHeadLocations),
+diff --git a/vanetza/asn1/its/MapData-addGrpC.h b/vanetza/asn1/its/MapData-addGrpC.h
+index 57a319245..6eeed4138 100644
+--- a/vanetza/asn1/its/MapData-addGrpC.h
++++ b/vanetza/asn1/its/MapData-addGrpC.h
+@@ -43,7 +43,7 @@ extern asn_TYPE_member_t asn_MBR_MapData_addGrpC_1[1];
+ #endif
+ 
+ /* Referred external types */
+-#include "SignalHeadLocationList.h"
++/* #include "SignalHeadLocationList.h" */
+ 
+ #endif	/* _MapData_addGrpC_H_ */
+ #include "asn_internal.h"
+diff --git a/vanetza/asn1/its/NodeSetXY.c b/vanetza/asn1/its/NodeSetXY.c
+index b07348a5b..0cdd012c0 100644
+--- a/vanetza/asn1/its/NodeSetXY.c
++++ b/vanetza/asn1/its/NodeSetXY.c
+@@ -6,6 +6,7 @@
+  */
+ 
+ #include "NodeSetXY.h"
++#include "NodeXY.h"
+ 
+ #if !defined(ASN_DISABLE_OER_SUPPORT)
+ asn_oer_constraints_t asn_OER_type_NodeSetXY_constr_1 CC_NOTUSED = {
+diff --git a/vanetza/asn1/its/NodeSetXY.h b/vanetza/asn1/its/NodeSetXY.h
+index c7bde7e41..1018d28a2 100644
+--- a/vanetza/asn1/its/NodeSetXY.h
++++ b/vanetza/asn1/its/NodeSetXY.h
+@@ -42,7 +42,7 @@ extern asn_per_constraints_t asn_PER_type_NodeSetXY_constr_1;
+ #endif
+ 
+ /* Referred external types */
+-#include "NodeXY.h"
++/* #include "NodeXY.h" */
+ 
+ #endif	/* _NodeSetXY_H_ */
+ #include "asn_internal.h"