SM6FBQ / HackRF clone - History

I2C: Device probe function I wrote, didn't need, but thought might be useful in the future.

PortaPack UI: Miscellaneous clean-up

Remove "portapack" arg to many static functions, no idea why I thought that was necessary.
Add PortaPack presence detect function using JTAG.
Create a "hackrf_ui_t" type that has function pointers to a specific UI implementation, returned by a UI detection function.

Pin setup: Break out JTAG configuration, rework to consider PortaPack.

Set 1V8 enable state before configuring pin function or to output mode

...to avoid glitching 1V8 enable voltage.

Set VAA_ENABLE# state before setting GPIO to output.

...to avoid glitching the output voltage.

Pin setup: Make GPIO direction reset the *first* step.

OperaCake code conflicts with PortaPack code, make compile-time conditional.

PortaPack: Conditionally claim JTAG pins in SCU #defines