firewall: Drop support for blocking P2P protocols.

firewall: Drop support for blocking P2P protocols.

The main P2P (peer-to-peer) aera has passed for several year now, so
this kind of feature is realy out-dated.

The feature only supports a handfull of P2P protocols (mostly unencrypted)
for applications, which have been superseeded by various other
applications and protocols.

So, this fairly is not longer required and safely can be dropped.

Signed-off-by: Stefan Schantl <stefan.schantl@ipfire.org>
Acked-by: Peter Müller <peter.mueller@ipfire.org>
Acked-by: Michael Tremer <michael.tremer@ipfire.org>