LU-6261 gnilnd: Add ability to bind scheduler threads to cpus.

LU-6261 gnilnd: Add ability to bind scheduler threads to cpus.

Added the module parameter thread_affinity which when enabled, will
bind the kgnilnd_sd_xx threads to cpus 1 through xx.
thread_affinity defaults to disabled.
Testing shows that enabling thread affinity will allow us to get
better small message performance with more scheduler threads.

Signed-off-by: Chris Horn <hornc@cray.com>
Change-Id: I5298c25cc21a1a856e4d84f1bca4f484449cd055
Reviewed-on: http://review.whamcloud.com/15432
Tested-by: Jenkins
Tested-by: Maloo <hpdd-maloo@intel.com>
Reviewed-by: James Simmons <uja.ornl@yahoo.com>
Reviewed-by: James Shimek <jshimek@cray.com>
Reviewed-by: Doug Oucharek <doug.s.oucharek@intel.com>
Reviewed-by: Oleg Drokin <oleg.drokin@intel.com>