V4L/DVB (4213): Cx88: cleanups

remove the following unused hooks:
- cx88-blackbird.c: cx88_ioctl_hook()
- cx88-blackbird.c: cx88_ioctl_translator()
make the following needlessly global functions static:
- cx88-tvaudio.c: cx88_detect_nicam()
remove the following unused EXPORT_SYMBOL's:
- cx88-cards.c: cx88_bcount
- cx88-cards.c: cx88_subids
- cx88-cards.c: cx88_idcount
- cx88-cards.c: cx88_card_list
- cx88-cards.c: cx88_card_setup
- cx88-core.c: cx88_start_audio_dma
- cx88-core.c: cx88_stop_audio_dma
- cx88-i2c.c: cx88_i2c_init

Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Michael Krufky <mkrufky@linuxtv.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>