Change detault regression build from opt to fast.
Change detault regression build from opt to fast.

--HG--
extra : convert_revision : b6db0254b73a97ab6e3685c90cc9cd30ea274d4f

Weil0ng/gem5,TUD-OS/gem5-dtu,gem5/gem5,zlfben/gem5,sobercoder/gem5,KuroeKurose/gem5,HwisooSo/gemV-update,KuroeKurose/gem5,austinharris/gem5-riscv,gedare/gem5,qizenguf/MLC-STT,powerjg/gem5-ci-test,rallylee/gem5,briancoutinho0905/2dsampling,joerocklin/gem5,qizenguf/MLC-STT,qizenguf/MLC-STT,SanchayanMaity/gem5,gedare/gem5,aclifton/cpeg853-gem5,kaiyuanl/gem5,rjschof/gem5,kaiyuanl/gem5,austinharris/gem5-riscv,TUD-OS/gem5-dtu,rjschof/gem5,austinharris/gem5-riscv,austinharris/gem5-riscv,powerjg/gem5-ci-test,powerjg/gem5-ci-test,HwisooSo/gemV-update,SanchayanMaity/gem5,yb-kim/gemV,zlfben/gem5,samueldotj/TeeRISC-Simulator,HwisooSo/gemV-update,KuroeKurose/gem5,gem5/gem5,KuroeKurose/gem5,sobercoder/gem5,zlfben/gem5,austinharris/gem5-riscv,samueldotj/TeeRISC-Simulator,rallylee/gem5,gem5/gem5,KuroeKurose/gem5,powerjg/gem5-ci-test,cancro7/gem5,rallylee/gem5,SanchayanMaity/gem5,SanchayanMaity/gem5,qizenguf/MLC-STT,joerocklin/gem5,qizenguf/MLC-STT,gem5/gem5,powerjg/gem5-ci-test,kaiyuanl/gem5,KuroeKurose/gem5,rjschof/gem5,samueldotj/TeeRISC-Simulator,gem5/gem5,zlfben/gem5,briancoutinho0905/2dsampling,gem5/gem5,TUD-OS/gem5-dtu,yb-kim/gemV,rallylee/gem5,zlfben/gem5,kaiyuanl/gem5,TUD-OS/gem5-dtu,aclifton/cpeg853-gem5,rjschof/gem5,sobercoder/gem5,joerocklin/gem5,briancoutinho0905/2dsampling,markoshorro/gem5,joerocklin/gem5,briancoutinho0905/2dsampling,markoshorro/gem5,HwisooSo/gemV-update,austinharris/gem5-riscv,briancoutinho0905/2dsampling,yb-kim/gemV,cancro7/gem5,sobercoder/gem5,joerocklin/gem5,aclifton/cpeg853-gem5,zlfben/gem5,TUD-OS/gem5-dtu,samueldotj/TeeRISC-Simulator,kaiyuanl/gem5,Weil0ng/gem5,aclifton/cpeg853-gem5,cancro7/gem5,cancro7/gem5,SanchayanMaity/gem5,austinharris/gem5-riscv,gedare/gem5,aclifton/cpeg853-gem5,samueldotj/TeeRISC-Simulator,KuroeKurose/gem5,powerjg/gem5-ci-test,rjschof/gem5,kaiyuanl/gem5,briancoutinho0905/2dsampling,yb-kim/gemV,HwisooSo/gemV-update,joerocklin/gem5,markoshorro/gem5,yb-kim/gemV,TUD-OS/gem5-dtu,markoshorro/gem5,samueldotj/TeeRISC-Simulator,yb-kim/gemV,cancro7/gem5,gedare/gem5,aclifton/cpeg853-gem5,markoshorro/gem5,cancro7/gem5,aclifton/cpeg853-gem5,qizenguf/MLC-STT,SanchayanMaity/gem5,HwisooSo/gemV-update,qizenguf/MLC-STT,cancro7/gem5,gem5/gem5,sobercoder/gem5,markoshorro/gem5,powerjg/gem5-ci-test,rallylee/gem5,rjschof/gem5,gedare/gem5,SanchayanMaity/gem5,rjschof/gem5,zlfben/gem5,joerocklin/gem5,Weil0ng/gem5,gedare/gem5,Weil0ng/gem5,yb-kim/gemV,TUD-OS/gem5-dtu,Weil0ng/gem5,briancoutinho0905/2dsampling,sobercoder/gem5,Weil0ng/gem5,markoshorro/gem5,sobercoder/gem5,gedare/gem5,HwisooSo/gemV-update,Weil0ng/gem5,joerocklin/gem5,rallylee/gem5,samueldotj/TeeRISC-Simulator,rallylee/gem5,kaiyuanl/gem5,yb-kim/gemV