`IOSync::mkOutputFor` does not work for a `Wire`

Error: "Clocks.bsv", line 1743, column 9: (G0005)
  The assertion `clock_crossing_rule' failed for rule
  `qsfp15_lpmode_clock_domain_crossing'
  because it has an implicit condition
  During elaboration of rule `clock_domain_crossing' at "Clocks.bsv", line
  1743, column 9.
  During elaboration of `qsfp15_lpmode' at
  "../hdl/boards/sidecar/qsfp_x32/QsfpX32ControllerTop.bsv", line 517, column
  24.
  During elaboration of `mkQsfpX32ControllerTop' at
  "../hdl/boards/sidecar/qsfp_x32/QsfpX32ControllerTop.bsv", line 233, column
  8.

The offending line here was something like:

qsfp15_lpmode = qsfps[15].lpmode;

Where qsfps[15].lpmode is a Wire driven by a Reg in a different module. Changing it to a RegU fixed the issue.

Start at IOSync::mkOutputFor and reproduce the failure using the Clocks.bsv case described in the report, including the assignment from qsfps[15].lpmode. Compare how Wire and RegU outputs are handled during elaboration; done means the Wire case no longer triggers the implicit-condition assertion and does not require the reported workaround.