[media] af0933: Don't go past arrays

X-Patchwork-Delegate: m.chehab@samsung.com
Fixes the following sparse warnings:
	drivers/media/dvb-frontends/af9033.c:295 af9033_init() error: buffer overflow 'clock_adc_lut' 11 <= 11
	drivers/media/dvb-frontends/af9033.c:300 af9033_init() error: buffer overflow 'clock_adc_lut' 11 <= 11
	drivers/media/dvb-frontends/af9033.c:584 af9033_set_frontend() error: buffer overflow 'coeff_lut' 3 <= 3
	drivers/media/dvb-frontends/af9033.c:595 af9033_set_frontend() error: buffer overflow 'clock_adc_lut' 11 <= 11

Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
Reviewed-by: Antti Palosaari <crope@iki.fi>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>