LU-9549 lnet: prevent assert on ln_state

lnet_peer_primary_nid() is called from lnet_parse. It checks
ln_state outside the net lock, causing a race condition
during shutdown where the code expects the state to be
running, but it's stopping or shutdown.

Fixed the issue by renaming lnet_peer_primary_nid() to
lnet_peer_primary_nid_locked(). This function is now called
when lnet_net_lock is held in lnet_parse().

In lnet_create_reply_msg() we already have access to the
msg_txpeer, so we lookup the primary_nid directly

Signed-off-by: Amir Shehata <amir.shehata@intel.com>
Change-Id: I0518cdbec95b38bd8690517320b601676ae259f0
Reviewed-on: https://review.whamcloud.com/27262


Tested-by: Jenkins
Tested-by: Maloo <hpdd-maloo@intel.com>
Reviewed-by: Doug Oucharek <doug.s.oucharek@intel.com>
Reviewed-by: Sonia Sharma <sonia.sharma@intel.com>
Reviewed-by: Olaf Weber <olaf.weber@hpe.com>
Reviewed-by: Oleg Drokin <oleg.drokin@intel.com>