Rough as in just not smooth....or rough in that there are sharp things that could cut a foot?
If you can walk on it barefoot, then the chickens can.....but if there are sharp points ridges that could cut skin, you might want to grind it down somehow.
A cut on a chickens foot can get infected causing a condition known as bumblefoot and can be nasty with a long treatment/healing time.
As long as the concrete does not hold water anywhere, I'd just cover it with 3-4 inches of pine shavings, but there are lots of options in bedding depending on how you plan to manage manure. Do a search on poop boards, will make your floor bedding lats much longer.