LU-16051 o2iblnd: detect link state to set fatal error on ni

LU-16051 o2iblnd: detect link state to set fatal error on ni

To avoid selecting lnet ni which corresponds to a downed link
for sending, add a mechanism for detecting ip-layer link events
in o2iblnd. On ip link up/down events, find corresponding
ni and toggle ni_fatal_error_on flag. This complements the
existing mechanism for ib-layer link event handling.

Lustre-change: https://review.whamcloud.com/48644
Lustre-commit: 30d73908087d5b2f0b18cce95826c4825c030ad4

Test-Parameters: trivial
Signed-off-by: Serguei Smirnov <ssmirnov@whamcloud.com>
Change-Id: I4720cd0a7bc577a522c7d40b54f821a4c12b670f
Reviewed-on: https://review.whamcloud.com/c/ex/lustre-release/+/49315
Tested-by: jenkins <devops@whamcloud.com>
Tested-by: Maloo <maloo@whamcloud.com>
Reviewed-by: Cyril Bordage <cbordage@whamcloud.com>
Reviewed-by: Andreas Dilger <adilger@whamcloud.com>