"fsm_export" pass: fix KISS file generation.

The KISS file format now follows the conventions specified in
"Logic Synthesis and Optimization Benchmarks User Guide", Version 3.0
by Saeyang Yang.

This change ensures interoperability with the "trfsmgen" program by Johann
Glaser.

Signed-off-by: Martin Schmölzer <martin.schmoelzer@student.tuwien.ac.at>