[media] media: drx39xyj - use drxj_set_lna_state() and remove duplicate LNA code

drx39xxj_set_lna() and drx39xxj_set_frontend() set LNA. Instead of
duplicating LNA configure code, change to use drxj_set_lna_state()
which sets LNA to the caller requested state (on or off).

Signed-off-by: Shuah Khan <shuah.kh@samsung.com>
Signed-off-by: Mauro Carvalho Chehab <m.chehab@samsung.com>