util/tools: fix prerelease_check build failure
util/tools: fix prerelease_check build failure

ajeddeloh/ignition,higebu/ignition,dgonyeo/ignition,AlexNPavel/ignition,ajeddeloh/ignition,dgonyeo/ignition,coreos/ignition,coreos/ignition,AlexNPavel/ignition,higebu/ignition,ajeddeloh/ignition,AlexNPavel/ignition,coreos/ignition,higebu/ignition,dgonyeo/ignition