vlog95: add support for emitting logic pull devices in a CA

If a logical pull device is converted into a CA then it is an assignment
with strength, so just emit the appropriate constant to get the correct
functionality (e.g. 1'b1 for a pull up and 1'b0 for a pull down).

Also add missing file/line information.
Merge branch 'master' of git://github.com/steveicarus/iverilog