don't provide juno-revision tag to LAVA

juno-revision tag is passed to LAVA which decides the board on
which tests will run, currently it is set R0. This causes a bottleneck
as we have different revisions of juno boards(R0/R1/R2) available in the
farm but jenkins job wait for R0 boards to be free and available.

This patch gets rid of providing a specific juno revision to LAVA as
TF-A CI does not need it.

Change-Id: Ibd949940ecd0dceaf04f02a218439044be90972a
Signed-off-by: Manish Pandey <manish.pandey2@arm.com>
diff --git a/script/gen_juno_linux_yaml.sh b/script/gen_juno_linux_yaml.sh
index 5413806..116a5c9 100755
--- a/script/gen_juno_linux_yaml.sh
+++ b/script/gen_juno_linux_yaml.sh
@@ -26,11 +26,19 @@
 }
 
 bootloader_prompt="${bootloader_prompt:-juno#}"
-juno_revision="${juno_revision:-juno-r0}"
 recovery_img_url="${recovery_img_url:-$(get_recovery_image_url)}"
 nfs_rootfs="${nfs_rootfs:-$juno_rootfs_url}"
 linux_prompt="${linux_prompt:-root@(.*):~#}"
 
+# Allow running juno tests on specific revision(r0/r1/r2).
+juno_revision="${juno_revision:-}"
+if [ ! -z "$juno_revision" ]; then
+        tags="tags:"
+        juno_revision="- ${juno_revision}"
+else
+        tags=""
+fi
+
 cat <<EOF
 device_type: juno
 job_name: tf-juno
@@ -38,8 +46,8 @@
 context:
   bootloader_prompt: $bootloader_prompt
 
-tags:
-- $juno_revision
+$tags
+$juno_revision
 
 timeouts:
   # Global timeout value for the whole job.