LU-12080 lnet: recovery event handling broken

LU-12080 lnet: recovery event handling broken

Don't increment health on unlink event.
If a SEND fails an unlink will follow so no need to do any
special processing on SEND event. If SEND succeeds then we
wait for the reply.
When queuing a message on the NI recovery queue only do so
if the MT thread is still running.

Lustre-change: https://review.whamcloud.com/34445
Lustre-commit: 5409e620e0256dc9b657f1c457541d7411b543cd

Test-Parameters: forbuildonly
Signed-off-by: Amir Shehata <ashehata@whamcloud.com>
Change-Id: I4877caebcac5cdfc35a59a18a3e3451b1f23cb0d
Reviewed-by: Olaf Weber <olaf.weber@hpe.com>
Reviewed-by: Sebastien Buisson <sbuisson@ddn.com>
Reviewed-by: Chris Horn <hornc@cray.com>
Signed-off-by: Minh Diep <mdiep@whamcloud.com>