SM6FBQ / HackRF clone - History

h1r9: check firmware running on r9 for r9 support

Previously we checked for OG support instead of r9 support because we
didn't yet have a way to tag firmware binaries with support for multiple
platforms.

h1r9: use single SSP configuration for MAX283x

During r9 hardware development it was thought that the MAX2839 would use
a different GPIO pin for chip select, but it ended up being the same pin
as is used for MAX2837 on other hardware revisions.

This takes the MAX283x abstraction a bit further and fixes a bug with
hackrf_debug -m.

h1r9: fix inverted spectrum on TX

Unify and clean up the firmware spectrum inversion handling for all
hardware platforms.