The cgminer in an antminer S5 is usually precompiled in firmware provided by bitmain and is based on an old forked version of cgminer. It is not supported by the official cgminer version and would be far from trivial to be supported and build a binary for the embedded controller of the S5. In short you cannot build the latest cgminer for S5. I built a temporary binary for the S5 a while ago which you can copy to the S5 here:
http://ck.kolivas.org/apps/cgminer/antminer/s5/
But it does not stay on the device across reboots and is based on 4.9.0 code. If you are not having trouble with your S5 there is little to gain by updating the software anyway, accepting the shortcomings of the forked older version from bitmain. Except in the case of mining on p2pool (which I recommend against with any antminer because of their code problems), most of the issues with their version of cgminer are not showstoppers.