[rom_ctrl] Remove an outdated TODO comment
[rom_ctrl] Remove an outdated TODO comment

When I was bringing this code up, the RTL didn't quite match the
original paper. Michael fixed the RTL in the meantime and I presumably
switched the Python around without removing the todo comment: oops!

Signed-off-by: Rupert Swarbrick <290093e2ad2515ed2f14d749293c8cf8e02ca274@lowrisc.org>

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