equiv_simple - try proving simple $equiv instances

yosys> help equiv_simple
equiv_simple [options] [selection]
This command tries to prove $equiv cells using a simple direct SAT approach.
verbose output
enable modelling of undef states
create shorter input cones that stop at shared nodes. This yields
simpler SAT problems but sometimes fails to prove equivalence.
disabling grouping of $equiv cells by output wire
-seq <N>
the max. number of time steps to be considered (default = 1)