V4L/DVB (7381): tuner: rename TUNER_PHILIPS_ATSC to TUNER_PHILIPS_FCV1236D

TUNER_PHILIPS_ATSC is an ambiguous name for a tuner.  Rename it to
TUNER_PHILIPS_FCV1236D to be more descriptive.

Signed-off-by: Michael Krufky <mkrufky@linuxtv.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>