Fix operators in UEFI post-install load check
    
    &! is not a thing, and os-autoinst has been warning us about
    this forever:
    
    Use of uninitialized value in bitwise and (&) at fedora/main.pm line 310.
    
    I just sorta didn't notice. Apparently this turned out to work,
    but it wasn't *right*. Let's do it this way instead.
    
    Signed-off-by: Adam Williamson <awilliam@redhat.com>