Set up more of the Luminary-specific signals, and stop cloning
a few of the JTAG defaults.  More comments too.

Still leaves the "dap info 0" bugs unresolved (presumably coupled
to this particular adapter family) where TPIU, ITM, DWT, and other
debug modules wrongly display as extra NVICs.

Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>