Ticket #48224 - redux 2 - logconv.pl should handle *.tar.xz, *.txz, *.xz log files
    
    https://fedorahosted.org/389/ticket/48224
    Reviewed by: nhosoi (Thanks!)
    Branch: 389-ds-base-1.3.3
    Fix Description: Use $? instead of $! to get pipe errors.
    Platforms tested: Fedora 21, RHEL 7.2 candidate
    Flag Day: no
    Doc impact: no
    
    (cherry picked from commit 29043c5716a1bc8364689d518cb4e35722eaaf77)
    (cherry picked from commit 0e31d818366e846f45c60b2c24bdb8026a82c048)