Tne only place that really needs the rtlsdr headers/libs is dump1090.c
itself. There is a dependency on rtlsdr_dev_t in the shared Modes
struct in dump1090.h, but this is a pointer type so we can just
use a dummy struct definition there to avoid the header dependency.
This lets us build faup1090 (for the piaware package) without
needing a useless librtlsdr-dev build-time dependency.
Create separate makefiles for dump1090, view1090 and ppup1090. These can
be run with the command line "make -f makedump1090", "make -f
makeview1019" and "make -f makeppup1090"
Pass dump1090 version number into ppup1090 uploader so that coaa1090.obj
doesn't need re-compiling between versions.
Remove ppup1090 from general Makefile - it's not intended for anything
other than RPi, so gives linker errors on other (non Linux raspian)
systems.
Updated the way socket handles are used in View1090 to maintain
compatibility between UNIX and Windows.
Added the initial attempt at a Planeplotter uploader