[ALSA] Fix misc bugs in i2c/others/ak4114.c

[ALSA] Fix misc bugs in i2c/others/ak4114.c

* correct register for 'IEC958 Non-PCM Bitstream', 'IEC958 DTS Bitstream'
  to use AK4114_REG_RCS0
* correct check for control name: if (strstr(kctl->id.name, 'Playback'))
* correct check: if (!chip->init) in snd_ak4114_external_rate
* added PCM control 'IEC958 PPL Lock Status'

Signed-off-by: Pavel Hofman <dustin@seznam.cz>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Jaroslav Kysela <perex@suse.cz>