ALSA: hda - Add Conexant CX20755/20756/20757 codec IDs

commit 42c364ace52ae6b4699105b39f2559c256b6cd4c upstream.

These are just compatible with other CX2075x codecs.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Cc: Weng Meiling <wengmeiling.weng@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>