Adding logic to undef IOP_MODEL before we include the env that may define it, that way the ENV can't be setting it

Fixes undeclared function warning when building awg client in DTT

In response to comments by Patrick

RPC results need to be cleared before calling an RPC function.

Version 4.0.1 and earlier had 4 testpoint interfaces instead of two.
This code autodetects which interfaces are used by awg
and switches to the appropriate interface

 * daq_data_types.h includes portableInline.h, so have cmake install that as well.

Previously in the adc read function, a slow card would lead to 'max_loops' dropping to 1 and staying there for future cards.
Fast ADCs read after slow ADCs would not have the output data properly decimated.