pmie_check: explicity set a umask appropriate for pmieconf
pmie_check: explicity set a umask appropriate for pmieconf

Ensure that a restrictive global root umask does not cause
pmie config files inaccessible to the $PCP_USER account.

Related to Red Hat BZ #1833647

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