s3: smbd: Only set xconn->smb1.negprot.done = true after supported_protocols[protocol...

s3: smbd: Only set xconn->smb1.negprot.done = true after supported_protocols[protocol].proto_reply_fn() succeeds.

Otherwise we can end up with negprot.done set, but
without smbXsrv_connection_init_tables() being called.

This can cause a client self-crash.

BUG: https://bugzilla.samba.org/show_bug.cgi?id=14205

Signed-off-by: Jeremy Allison <jra@samba.org>
Reviewed-by: Volker Lendecke <vl@samba.org>
Autobuild-User(master): Jeremy Allison <jra@samba.org>
Autobuild-Date(master): Wed Dec  4 21:27:24 UTC 2019 on sn-devel-184

(cherry picked from commit 8db0c1bff6f42feabd2e4d9dfb13ae12cc29607b)