Define RVFI as cva6 parameter
Created by: JeanRochCoulon
To remove the ifdef directives from the code, RVFI is defined as cva6 parameter. This PR superseed the https://github.com/openhwgroup/cva6/pull/1275
WARNING: this PR is the little brother of https://github.com/openhwgroup/core-v-verif/pull/2019. To be merged at the same time to keep cva6 functional.
Signed-off-by: Jean-Roch Coulon jean-roch.coulon@thalesgroup.com