LINUX: Ignore 'offender' in error queue processing

LINUX: Ignore 'offender' in error queue processing

The 'offender' is who generated the error, possibly who sent us an
icmp packet (the given 'port' will be 0). What we want is the peer
that is actually unavailable, which is already in the 'addr' variable
we received from the recvmsg itself.

Change-Id: I930293ca14f0e13ba09ee94b5a5d9cdc0f321743
Reviewed-on: http://gerrit.openafs.org/8119
Tested-by: BuildBot <buildbot@rampaginggeek.com>
Reviewed-by: Derrick Brashear <shadow@your-file-system.com>