Fix #664 by compiling on musl libc
Fix #664 by compiling on musl libc

See http://stackoverflow.com/questions/6381526/what-is-the-significance-of-caddr-t-and-when-is-it-used and https://github.com/metachris/RPIO/issues/40 for more details.
qbit/psutil,jorik041/psutil,giampaolo/psutil,0-wiz-0/psutil,jamesblunt/psutil,jorik041/psutil,qbit/psutil,msarahan/psutil,cloudbase/psutil,jamesblunt/psutil,giampaolo/psutil,msarahan/psutil,qbit/psutil,jorik041/psutil,0-wiz-0/psutil,cloudbase/psutil,jamesblunt/psutil,mrjefftang/psutil,mrjefftang/psutil,cloudbase/psutil,msarahan/psutil,mrjefftang/psutil