Rx: Change minimum peer timeout to 2ms

Rx: Change minimum peer timeout to 2ms

The previous value, 350ms, is historical.  Now that networks are
so much faster, an artificially high timeout value when backed off
results in an extremely long delay before communication can resume.

Change-Id: I6207fb3e5c26a36704abc1f9210af53e0ff1fae6
Reviewed-on: http://gerrit.openafs.org/2815
Tested-by: BuildBot <buildbot@rampaginggeek.com>
Reviewed-by: Derrick Brashear <shadow@dementia.org>
(cherry picked from commit c77f2f1369fead87acb440134213ebf6d23f8fd7)
Reviewed-on: http://gerrit.openafs.org/2824
Tested-by: Derrick Brashear <shadow@dementia.org>