Changes

hnbgw: Get rid of pars param in void_fn

Store pars into component field "g_pars" before caling void_fn.
This simplifies ConnHdlr test functions and also avoids potential
problems modifying pars vs g_pars.
This is the same as we do in lots of other testsuites.

Change-Id: I674b2a6a6a0e39f2904f9125783180da8ade5f44