LU-9667 lnet: Add LNet peer sysfs structure

LU-9667 lnet: Add LNet peer sysfs structure

Adding APIs to create ksets, kobjects
and the attribute files for peer sysfs directory
structure.

Callback functions for the LNet Peer attributes
are added to be used to display peer statistics.

Change-Id: I39d57806dd3b94fc5924e7e9525b79b4e647006e
Test-Parameters: trivial
Signed-off-by: Sonia Sharma <sonia.sharma@intel.com>
Reviewed-on: https://review.whamcloud.com/32579
Reviewed-by: James Simmons <uja.ornl@yahoo.com>
Reviewed-by: Amir Shehata <ashehata@whamcloud.com>
Tested-by: Jenkins
Tested-by: Maloo <maloo@whamcloud.com>
Reviewed-by: Sonia Sharma <sharmaso@whamcloud.com>