nginx-odp-dpdk.yaml: use sh-test-lib functions

We will now use the add_key and add_repo functions provided by
sh-test-lib, also the repository used can be specified as one of the
test parameters.

Installation of release-specific packages has been removed. Any extra
packages from other repositories than the ones under test (currently
jessie-backports) will have to be installed by the calling LAVA job.
This way this test definition will work on newer versions of the
distribution without having to change anything.

See this lava job for an example:
https://lng.validation.linaro.org/scheduler/job/17262/multinode_definition

Change-Id: I6119b451c4921afde861f8b3473cdfdca140d3f5
Signed-off-by: Josep Puigdemont <josep.puigdemont@linaro.org>
diff --git a/automated/linux/nginx-server/nginx-odp-dpdk.yaml b/automated/linux/nginx-server/nginx-odp-dpdk.yaml
index 9f65e0b..749bde5 100644
--- a/automated/linux/nginx-server/nginx-odp-dpdk.yaml
+++ b/automated/linux/nginx-server/nginx-odp-dpdk.yaml
@@ -25,14 +25,15 @@
 params:
     MAX_CORES: 0
     VLAND_NAME: vlan_one
+    DEB_REPO_URL: http://deb.opendataplane.org
+    DEB_REPO_KEY_URL: http://deb.opendataplane.org/odp.key
 
 run:
     steps:
-        - wget -O - http://deb.opendataplane.org/odp.key|sudo apt-key add -
-        - echo "deb http://deb.opendataplane.org jessie main" > /etc/apt/sources.list.d/odp.list
-        - echo "deb http://ftp.debian.org/debian jessie-backports main" > /etc/apt/sources.list.d/backports.list
+        - . automated/lib/sh-test-lib
+        - add_key "$DEB_REPO_KEY_URL"
+        - add_repo "$DEB_REPO_URL"
         - apt-get update
-        - apt-get -t jessie-backports install -y libssl1.0.0 libssl-dev
         - sysctl -w vm.nr_hugepages=1024
         - modprobe uio
         - apt-get install -y dpdk-igb-uio-dkms dpdk pciutils