build-unit-test-docker: New phosphor-dbus flag

Now that the org.open_power D-Bus interfaces moved into
phosphor-dbus-interfaces, a configure option is needed for
phosphor-dbus-interfaces to enable them.

(Cannot remove openpower-dbus-interfaces yet as many repos
still look for it.)

Change-Id: I83f31383ae34d844413d810028d405dbbb7c207c
Signed-off-by: Matt Spinler <spinler@us.ibm.com>
diff --git a/build-unit-test-docker.sh b/build-unit-test-docker.sh
index f120539..5884213 100755
--- a/build-unit-test-docker.sh
+++ b/build-unit-test-docker.sh
@@ -392,7 +392,7 @@
 RUN curl -L https://github.com/openbmc/phosphor-dbus-interfaces/archive/${PKG_REV['openbmc/phosphor-dbus-interfaces']}.tar.gz | tar -xz && \
 cd phosphor-dbus-interfaces-* && \
 ./bootstrap.sh && \
-./configure ${CONFIGURE_FLAGS[@]} && \
+./configure ${CONFIGURE_FLAGS[@]} --enable-openpower-dbus-interfaces && \
 make -j$(nproc) && \
 make install