fixes #11608 - permit Foreman/passenger_t to bind to VNC ports

[domcleal]

During initialisation of the websockify process for consoles, Foreman
now binds to the VNC ports to check if they're free first.

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An EL7.1 build: https://fedorapeople.org/~domcleal/foreman/rpm_11608/foreman-selinux-1.10.0-0.develop.201509180834gitbd557ae3.el7.centos.noarch.rpm

# sesearch --allow -s passenger_t -t vnc_port_t -c tcp_socket -p name_bind
Found 1 semantic av rules:
   allow passenger_t vnc_port_t : tcp_socket name_bind ; 

[lzap]

Merged as d3a9081, thank you!