BUILD: Make chown of files to sssd user non-fatal
    
    In build environments, we can't assume the sssd user will be created
    prior to installing the package, so we can't chown the files.
    
    RPM will own the files instead in this case.
    
    Related:
    https://fedorahosted.org/sssd/ticket/2370
    
    Reviewed-by: Lukáš Slebodník <lslebodn@redhat.com>