V4L/DVB (8114): cx18: Improve Raptor card audio input routing defintions

cx18: Improved Raptor card audio input routing defintions, so that muxer values
matched cx18_gpio() values for tuner, line in 1, and radio and added LED
indication of selected audio input.  Audio line in 2 doesn't work as it uses
the not yet supported 2nd I2S port.  Tuner/FM Radio AF is mono until SIF
support is fixed.

Signed-off-by: Andy Walls <awalls@radix.net>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>