contrib/jenkins.sh: run "make maintainer-clean"

Related: OS#3047
Change-Id: Ieae88eec72801e143daa631e7d01a5e11e9befae
diff --git a/contrib/jenkins.sh b/contrib/jenkins.sh
index 7ec1463..f1779dc 100755
--- a/contrib/jenkins.sh
+++ b/contrib/jenkins.sh
@@ -41,5 +41,6 @@
 DISTCHECK_CONFIGURE_FLAGS="--with-pcap-config=/bin/true" \
         PCAP_LIBS="-lpcap" PCAP_CFLAGS="" \
         $MAKE distcheck || cat-testlogs.sh
+$MAKE maintainer-clean
 
 osmo-clean-workspace.sh