doc: Fix fileserver synopsis

doc: Fix fileserver synopsis

The fileserver synopsis was missing the leading 'fileserver' before
the options list. This causes the options list to not be interpreted
as POD, and so you get a lot of ugly unprocessed POD markup in the man
page. Fix that.

Reviewed-on: http://gerrit.openafs.org/3301
Tested-by: BuildBot <buildbot@rampaginggeek.com>
Reviewed-by: Derrick Brashear <shadow@dementia.org>
(cherry picked from commit 4669a55b58ddb6905424c4f8123d7e631f52eb35)

Change-Id: Ib545b1d7c09dd2ce450517df1b0c0d20248c9161
Reviewed-on: http://gerrit.openafs.org/4010
Tested-by: BuildBot <buildbot@rampaginggeek.com>
Reviewed-by: Derrick Brashear <shadow@dementia.org>