test if exim can create dirs under /var/spool/exim/input/
    
    A recently filed customer report revealed that SELinux prevents
    the exim's sendmail program from creating new directories under the
    /var/spool/exim/input/ directory. The TC reproduces the situation.
    
    In order to support the whole functionality of exim (especially the
    split_spool_directory configuration option), I believe that SELinux
    policy should allow the action. The TC looks for appropriate policy
    rules and file context patterns.
    
    The TC covers RHEL-14110 and RHEL-14186.