LU-864 test: Hostname name doesn't equal NID and use facet_mntpt

LU-864 test: Hostname name doesn't equal NID and use facet_mntpt

On our test systems the hostname of the servers is on the
ethernet fabric and for lustre we use infiniband separately.
Currently several test will not run because of the assumption
that lustre will use the same fabric and we use to login and
manage the server. This patch allows one to grab the real NIDs
instead of assuming its "hostname"@NETTYPE. The second part of
the patch removes using $MOUNT% directly and uses facet_mntpt.
The reason being is on our system the mount points are different
on our servers from our clients. MOUNT is assumed to be the same
for clients and the servers. This patch allows test to work if
that is not the case.

Signed-off-by: James Simmons <uja.ornl@gmail.com>
Change-Id: I49f365561e341d44ace4c961fcae8b871dce7407
Reviewed-on: http://review.whamcloud.com/248
Tested-by: Hudson
Reviewed-by: Yu Jian <yujian@whamcloud.com>
Tested-by: Maloo <whamcloud.maloo@gmail.com>
Reviewed-by: Andreas Dilger <adilger@whamcloud.com>