ALSA: Add definitions for the bits in IEC958 subframe

ALSA: Add definitions for the bits in IEC958 subframe

The IEC958 subframe format SNDRV_PCM_FMTBIT_IEC958_SUBFRAME_LE are used
in HDMI and DisplayPort to describe the audio stream, but hardware device
may need to reorder the IEC958 bits for internal transmission, so need
these standard bits definitions for IEC958 subframe format.

Signed-off-by: Shengjiu Wang <shengjiu.wang@nxp.com>
Reviewed-by: Takashi Iwai <tiwai@suse.de>
Tested-by: Alexander Stein <alexander.stein@ew.tq-group.com>
Signed-off-by: Liu Ying <victor.liu@nxp.com>
Link: https://lore.kernel.org/r/20250923053001.2678596-3-shengjiu.wang@nxp.com