[rom_ctrl, dv] Upgrades to collect functional coverage
[rom_ctrl, dv] Upgrades to collect functional coverage

Updates made to coverage interface as design has evolved more.
Removed cp_rom_invalid_condition covergroup as there is no
pwrmgr_data_o.invalid bit. Corrupting good and done signals to get the
invalid coverage doesn't make sense for the design at this stage.

Signed-off-by: Prajwala Puttappa <d42da9c1e7c0c7ddf8c0244ff16e57febc9395a0@lowrisc.org>

lowRISC/opentitan,lowRISC/opentitan,lowRISC/opentitan,lowRISC/opentitan,lowRISC/opentitan,lowRISC/opentitan