LU-10452 lnet: cleanup YAML output

LU-10452 lnet: cleanup YAML output

The level of verbosity is high when exporting the YAML configuration
for the purposes of storing it to reconfigure a node. This patch
eliminates the unnecessary YAML lines which are not needed when
reconfiguring a node, such as statistics, status, etc.

Test-Parameters: trivial
Signed-off-by: Amir Shehata <amir.shehata@intel.com>
Change-Id: Ie57c761415cfb0ceee8b2dbc0b293e85ae415685
Reviewed-on: https://review.whamcloud.com/30845
Tested-by: Jenkins
Tested-by: Maloo <hpdd-maloo@intel.com>
Reviewed-by: Doug Oucharek <dougso@me.com>
Reviewed-by: Andreas Dilger <andreas.dilger@intel.com>
Reviewed-by: James Simmons <uja.ornl@yahoo.com>
Reviewed-by: Oleg Drokin <oleg.drokin@intel.com>