LU-13837 lnet: Introduce constant for net ID of LNET_NID_ANY

LU-13837 lnet: Introduce constant for net ID of LNET_NID_ANY

This patch adds a new constant, LNET_NET_ANY, to represent the net
ID of the LNET_NID_ANY wildcard NID.

Test-Parameters: trivial
HPE-bug-id: LUS-9122
Signed-off-by: Chris Horn <chris.horn@hpe.com>
Change-Id: I4b4d9e70ba2826843c6585ad5a9e365799face65
Reviewed-on: https://review.whamcloud.com/39544
Tested-by: jenkins <devops@whamcloud.com>
Reviewed-by: Andreas Dilger <adilger@whamcloud.com>
Tested-by: Maloo <maloo@whamcloud.com>
Reviewed-by: Neil Brown <neilb@suse.de>