Use the helpers to parse the level and description fields in
incoming alerts. "Warning" alerts are discarded, and "fatal"
alerts mean the session is no longer valid.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Link: https://lore.kernel.org/r/169047944747.5241.1974889594004407123.stgit@oracle-102.nfsv4bat.orgSigned-off-by: Jakub Kicinski <kuba@kernel.org>