src/pmdas/root/lxc.c: change from popen() to __pmProcessPipe() et al
src/pmdas/root/lxc.c: change from popen() to __pmProcessPipe() et al

adfernandes/pcp,adfernandes/pcp,adfernandes/pcp,adfernandes/pcp,adfernandes/pcp,adfernandes/pcp,adfernandes/pcp,adfernandes/pcp