V4L/DVB (3840): Create standalone fe_lgh064f header

move all pll_set functions for lg-tdvs-h06xf atsc tuners to a standalone header

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