LU-5026 obdclass: Add lbug_on_eviction option

Add an lbug_on_eviction sysfs interface.  When it is set to a non-zero
value on a client, it will cause the client to LBUG whenever it is
evicted by the server. Note, an MDS is a client to OSTs, and every
server is a client of MGS. Thus, it is probably desireable to leave
this set to zero on servers.

Change-Id: I2f694e4bc1b1ec9daf52f8a6ac46ad87f40f810f
Cray-bug-id: LUS-2591
Signed-off-by: Ryan Haasken <haasken@cray.com>
Signed-off-by: Chris Horn <hornc@cray.com>
Reviewed-on: https://review.whamcloud.com/10257
Tested-by: Jenkins
Reviewed-by: Andreas Dilger <adilger@whamcloud.com>
Tested-by: Maloo <hpdd-maloo@intel.com>
Reviewed-by: Alexandr Boyko <c17825@cray.com>
Reviewed-by: Oleg Drokin <green@whamcloud.com>