Accept OVN_SRCDIR passed to tox

Make it possible to pass OVN_SRCDIR to tox so that compiling isn't
necessary if you already have a functional OVN_SRCDIR, e.g. if
deploying with devstack with OVN_BUILD_FROM_SOURCE=True

Change-Id: If966de7dec93ba71f05d48e1d58d3369ce5f4e0a
Signed-off-by: Terry Wilson <twilson@redhat.com>

tools/setup-ovs.sh

@@ -13,4 +13,6 @@ if [ "$OVN_SRCDIR" -a ! -d "$OVN_SRCDIR" ]; then
     popd
     ./boot.sh && PYTHON=/usr/bin/python ./configure && make -j$(($(nproc) + 1))
     popd
+else
+    echo "Using OVN branch $OVN_BRANCH in $OVN_SRCDIR"
 fi

tox.ini

@@ -62,9 +62,9 @@ commands = oslo_debug_helper {posargs}
 [testenv:functional]
 setenv = {[testenv]setenv}
          OS_TEST_PATH=./ovsdbapp/tests/functional
-         OVN_SRCDIR={envdir}/src/ovn
-         OVS_SRCDIR={envdir}/src/ovn/ovs
-         VTEP_SRCDIR={envdir}/src/ovn/ovs/vtep
+         OVN_SRCDIR={env:OVN_SRCDIR:{envdir}/src/ovn}
+         OVS_SRCDIR={env:OVN_SRCDIR:{envdir}/src/ovn}/ovs
+         VTEP_SRCDIR={env:OVN_SRCDIR:{envdir}/src/ovn}/ovs/vtep
          OVN_BRANCH={env:OVN_BRANCH:}
 passenv = KEEP_VENV
 commands =