Migrate to libyang2

Also update buildroot to latest master:
- the sdbus-cpp version bump patch has been removed, because upstream
  now bumped it to an even newer version

- Fix RAUC not able to start a service
(https://github.com/buildroot/buildroot/commit/72308ab9a32de6e8b4b23e42f115ed5ee87e5f33)

Depends-on: https://cesnet-gerrit-czechlight/c/CzechLight/netconf-cli/+/4539
Depends-on: https://gerrit.cesnet.cz/c/CzechLight/netconf-cli/+/4539
Depends-on: https://cesnet-gerrit-czechlight/c/CzechLight/rousette/+/5391
Depends-on: https://gerrit.cesnet.cz/c/CzechLight/rousette/+/5391
Depends-on: https://gerrit.cesnet.cz/c/CzechLight/cla-sysrepo/+/5292
Depends-on: https://cesnet-gerrit-czechlight/c/CzechLight/velia/+/5237
Depends-on: https://gerrit.cesnet.cz/c/CzechLight/velia/+/5237
Change-Id: I6edc19f35accfd41a4b32f7b396981d470e0c07b
diff --git a/configs/czechlight_clearfog_defconfig b/configs/czechlight_clearfog_defconfig
index e4b4bd4..152f0b6 100644
--- a/configs/czechlight_clearfog_defconfig
+++ b/configs/czechlight_clearfog_defconfig
@@ -67,6 +67,7 @@
 BR2_PACKAGE_AUDIT=y
 BR2_PACKAGE_DDRESCUE=y
 BR2_PACKAGE_RAUC=y
+BR2_PACKAGE_RAUC_DBUS=y
 BR2_PACKAGE_RAUC_NETWORK=y
 BR2_PACKAGE_SYSTEMD_JOURNAL_REMOTE=y
 BR2_PACKAGE_SYSTEMD_COREDUMP=y