Like a punch in the face, ‘Sharp Dressed Man’ explodes out of the speakers, a sleek, streamlined beast of a song, riding a pulsating electric beat into the horizon. Never mind the suits, the beards, and the cool cars, ZZ Top’s legacy to popular music is making hard rock that you can dance to. Trying to sound ‘modern’ is the kiss of death, but when you do it as good as this, you’re onto a winner. Eliminator, ‘Sharp Dressed Man’s parent album, kinda came out of nowhere. ZZ Top had been a very successful boogie-rock band, churning out blues riffs,…