nfsd: fix courtesy client with deny mode handling in nfs4_upgrade_open
The nested if statements here make no sense, as you can never reach
"else" branch in the nested statement. Fix the error handling for
when there is a courtesy client that holds a conflicting deny mode.
Fixes: 3d6942715180 ("NFSD: add support for share reservation conflict to courteous server") Reported-by: 張智諺 <cc85nod@gmail.com> Signed-off-by: Jeff Layton <jlayton@kernel.org> Reviewed-by: Dai Ngo <dai.ngo@oracle.com> Signed-off-by: Chuck Lever <chuck.lever@oracle.com>