Fixed the name of Cirros image used in OpenStack. The image name
is written in lowercase letters.
JIRA: YARDSTICK-842
Change-Id: Iff0b494125be61a055da753eaf57903b64f18509
Signed-off-by: Rodolfo Alonso Hernandez <rodolfo.alonso.hernandez@intel.com>
         CIRROS_IMAGE_PATH="/home/opnfv/images/cirros-d161201-aarch64-disk.img"
         EXTRA_PARAMS="--property hw_video_model=vga --property short_id=ubuntu16.04"
     else
-        CIRROS_IMAGE_VERSION="Cirros-0.3.5"
+        CIRROS_IMAGE_VERSION="cirros-0.3.5"
         CIRROS_IMAGE_PATH="/home/opnfv/images/cirros-0.3.5-x86_64-disk.img"
     fi