rpcrt4: Ensure that only the IP/IPv6 address families are considered in rpcrt4_protseq_ncacn_ip_tcp_open_endpoint/rpcrt4_ncacn_ip_tcp_open.

Return RPC_S_INVALID_ENDPOINT_FORMAT if a NULL endpoint is passed into
RpcServerUseProtseqEp{,Ex}{A,W}.

It doesn't really matter if lighting is enabled or not if we don't have
position data.

These are essentially unused, and mostly just complicate the code.

rpcrt4: Dynamically allocate the buffer if the fixed size one isn't large enough. Don't return an inappropriate error if we fail to get the status text, it's only used for diagnostics.