Add header comment for POSIX compliant scripts
    
    upstream: fedora
    resolves: bz2003832
    conflict: none
    
    commit ee337c6f497a92a12848a85dcce468c1a4bcd14f
    Author: Kairui Song <kasong@redhat.com>
    Date:   Mon Sep 13 03:38:14 2021 +0800
    
        Add header comment for POSIX compliant scripts
    
        To make things cleaner and more human readable, add a short comment for
        the POSIX scripts.
    
        Signed-off-by: Kairui Song <kasong@redhat.com>
        Acked-by: Philipp Rudo <prudo@redhat.com>
    
    Signed-off-by: Tao Liu <ltao@redhat.com>