Request upgrade of devel/yosys

[Mayuresh <mayuresh%acm.org@localhost>]

pkgsrc version, 0.38, is 7 releases old now - current being 0.45

This is an evolving package with frequent releases. Request to upgrade to
the latest.

I attempted this, though ran into following errors during build of abc:

    ld: cannot find -lreadline
    ld: cannot find -lffi
    ld: cannot find -ltcl86


buildlinks look alright. So not sure why these should occur.

-- 
Mayuresh