LU-14540 o2iblnd: Use REMOTE_DROPPED for ECONNREFUSED

LU-14540 o2iblnd: Use REMOTE_DROPPED for ECONNREFUSED

ECONNREFUSED means that we received a response from the remote end,
so setting the LNet health status to REMOTE_DROPPED is more
appropriate than setting LOCAL_DROPPED. Using REMOTE_DROPPED will
decrement the peer NI health and allow us to try other peer NIs for
future sends.

Decrementing the peer NI health will also result in routes being
marked down, as appropriate, for cases where a router has refused the
connection request.

Lustre-commit: f9d837b479232bfc4f271f23cd3729ca67cb6c1d
Lustre-change: https://review.whamcloud.com/42114

Test-Parameters: trivial
HPE-bug-id: LUS-9853
Signed-off-by: Chris Horn <chris.horn@hpe.com>
Change-Id: I8190f5d78a76ec25553908c4f215362c0c2051fc
Reviewed-by: James Simmons <jsimmons@infradead.org>
Reviewed-by: Alexander Boyko <alexander.boyko@hpe.com>
Reviewed-on: https://review.whamcloud.com/44248
Tested-by: jenkins <devops@whamcloud.com>
Tested-by: Maloo <maloo@whamcloud.com>
Reviewed-by: Andreas Dilger <adilger@whamcloud.com>