[hpsdr] multiple Rx in Mercury

[Bruce Walker]

I know there was discussion many months ago about implementing
multiple receivers in Mercury.  Now that I actually have one to
experiment with, I'm wondering where any such efforts stand.  I'm
interested in experimenting with the FPGA code myself, but if anyone
has an implementation to use or build on, all the better.

For my personal desires, I would be content ending up the same overall
sample rate between Mercury and PC (192k/96k/48k), but I would like to
be able to interleave different channels (e.g., 8 channels of 12ks/s
I/Q rather than one 96ks/s) if there is room.

--bruce W1BW