LU-13903 utils: separate out server code for wiretest

LU-13903 utils: separate out server code for wiretest

Both the kernel and userland utility wiretest is used by both
client and server to validate data being sent over the network.
Make userland  wiretest buildable on the native Linux client
which lacks server specific data structures. Use of the UAPI
values to hardern testing of user land data passed to the
kernel.

Change-Id: I30efc8bf42ac461bab5a4371e940a027a23d12c9
Signed-off-by: James Simmons <jsimmons@infradead.org>
Reviewed-on: https://review.whamcloud.com/43873
Tested-by: jenkins <devops@whamcloud.com>
Reviewed-by: Andreas Dilger <adilger@whamcloud.com>
Tested-by: Maloo <maloo@whamcloud.com>
Reviewed-by: Neil Brown <neilb@suse.de>
Reviewed-by: Oleg Drokin <green@whamcloud.com>