test if systemd-modules-load can read files under /sys/firmware/efi
    
    According to several BZ reports, the systemd-modules-load program
    wants to read /sys/firmware/efi/efivars/SecureBoot-* files.
    Unfortunately, SELinux policy denies that access.
    The TC reproduces the issue on machines where the EFI variable FS
    is mounted (the /sys/firmware/efi/efivars/ directory exists).
    
    I believe the access is needed for correct function of the
    systemd-modules-load service. The TC looks for appropriate
    policy rule.
    
    The TC covers BZ#1819161 and its duplicates.