NFSD: Enhance the nfsd_cb_setup tracepoint

[ Upstream commit 9f57c606 ]

Display the transport protocol and authentication flavor so admins
can see what they might be getting wrong.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>