Sync dependencies

pybind11 is not used in any project yet, but we have to bring it in via
Zuul because it's a (transitive) git submodule. Let's pin the SCM
version for a future Buildroot package as well while we're at this.

Change-Id: I0b09ca4c9d60e95c7d1a62c1f11f7e7a53bf2841
diff --git a/dev-setup-git.sh b/dev-setup-git.sh
index f9d9baf..9cfb294 100755
--- a/dev-setup-git.sh
+++ b/dev-setup-git.sh
@@ -21,6 +21,7 @@
 CLA_SYSREPO_OVERRIDE_SRCDIR = ${CZECHLIGHT_BR2_EXT_LOC}/submodules/cla-sysrepo
 NETCONF_CLI_OVERRIDE_SRCDIR = ${CZECHLIGHT_BR2_EXT_LOC}/submodules/netconf-cli
 GAMMARUS_OVERRIDE_SRCDIR = ${CZECHLIGHT_BR2_EXT_LOC}/submodules/gammarus
+PYBIND11_OVERRIDE_SRCDIR = ${CZECHLIGHT_BR2_EXT_LOC}/submodules/pybind11
 EOF
 
 # We have to run make first so that the proxy Makefile is created and the BR2_EXTERNAL is remembered