opal-ci: Drop unneded reference to ubuntu 12.04
opal-ci: Drop unneded reference to ubuntu 12.04

Signed-off-by: Stewart Smith <ec31ab75ddf977353c8f660f92ea8b23f64aef25@linux.ibm.com>

qemu/skiboot,shenki/skiboot,open-power/skiboot,legoater/skiboot,qemu/skiboot,shenki/skiboot,legoater/skiboot,open-power/skiboot,stewart-ibm/skiboot,stewart-ibm/skiboot,qemu/skiboot,stewart-ibm/skiboot,shenki/skiboot,qemu/skiboot,open-power/skiboot,open-power/skiboot,legoater/skiboot,legoater/skiboot,shenki/skiboot,shenki/skiboot,legoater/skiboot,qemu/skiboot,open-power/skiboot