Two types of non-inverting 2-way muxes. The v0 muxes
are minimum width but slow on pin s
as the inverting path to pin z
has three stage delays. The v2 mux uses transfer gates for
the best speed but is bigger.
z:((a0*s')+(a1*s))
cell width
power
Generic 0.13um typical timing (ps & ps/fF),
pin s.