Pattern matching glitch patch from upstream
    
    See http://lists.gnu.org/archive/html/bug-bash/2011-02/msg00136.html
    
    var='[hello'
    echo "${var//[/}"
    
    With bash 4.1 it outputs hello but with 4.2 it outputs [hello
    
    This commit fixes it.
    
    Signed-off-by: Roman Rakus <rrakus@redhat.com>