aci: remove dead code
aci: remove dead code

This is not useful, we can introduce as necessary if we decide to
implement some of this behaviour within the spec tooling (for now it's
being implemented by e.g. Rocket directly)

stufflebear/spec,jonboulle/spec,3ofcoins/appc-spec,dgonyeo/spec,alban/appc-spec,iaguis/appc-spec,tklauser/spec,krnowak/appc-spec,alban/appc-spec,jonboulle/spec,dgonyeo/spec,tklauser/spec,appc/spec,apcera/appc-spec,appc/spec,squeed/spec,tklauser/spec,squeed/spec,stufflebear/spec,dgonyeo/spec,iaguis/appc-spec,dustymabe/spec,zenlinTechnofreak/spec,endocode/appc-spec,apcera/appc-spec,ChengTiesheng/spec,ChengTiesheng/spec,craimbert/spec,dustymabe/spec,appc/spec,alban/appc-spec,krnowak/appc-spec,marineam/spec,marineam/spec,3ofcoins/appc-spec,craimbert/spec,krnowak/appc-spec,zenlinTechnofreak/spec,endocode/appc-spec,yifan-gu/spec,apcera/appc-spec,jonboulle/spec,marineam/spec,squeed/spec,iaguis/appc-spec,yifan-gu/spec,craimbert/spec,yifan-gu/spec,endocode/appc-spec,zenlinTechnofreak/spec,ChengTiesheng/spec,stufflebear/spec,dustymabe/spec,3ofcoins/appc-spec