LU-13642 lnet: Allow dynamic IP specification

LU-13642 lnet: Allow dynamic IP specification

Currently you can setup an NI only using the device interface.
It is possible that a device interface has more than one IP
address. This change updates lnet_net_cmd() to setup an NI using
a specific network address.

For further reference please read

IP specification in LNet
https://wiki.whamcloud.com/display/LNet/IP+specification+in+LNet

Test-Parameters: trivial testlist=sanity-lnet
Change-Id: I2c456790fe9534bbfe02b0330cce73e80318cc1c
Signed-off-by: James Simmons <jsimmons@infradead.org>
Reviewed-on: https://review.whamcloud.com/c/fs/lustre-release/+/53605
Tested-by: jenkins <devops@whamcloud.com>
Tested-by: Maloo <maloo@whamcloud.com>
Reviewed-by: Chris Horn <chris.horn@hpe.com>
Reviewed-by: Frank Sehr <fsehr@whamcloud.com>
Reviewed-by: Oleg Drokin <green@whamcloud.com>