[topgen] Demote message about xbar connections from warning to info
[topgen] Demote message about xbar connections from warning to info

This is just how we wire up our chip at the moment, so a warning
doesn't seem like the right thing to do!

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

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