first stages of removing struct cli_state* and uint16 fnum from all

first stages of removing struct cli_state* and uint16 fnum from all
msrpc client code.  the intent is to hide / abstract / associate
connection info behind policy handles.

this makes the msrpc functions look more and more like their nt equivalents.

who-hou!
(This used to be commit c01b18e632aede6fce7264ef6971d7ddba945cfb)