In rc.firewall, make it clear that this is the setup for IPFW(4), and not for the sundry other firewalls in the system.
In rc.firewall, make it clear that this is the setup for IPFW(4), and not
for the sundry other firewalls in the system.

MFC after:	3 days
Submitted by:	Richard dot Clayton at cl dot cam dot ac dot uk

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