ALSA: hda/proc - print DP-MST connections

To help in debugging issues with DisplayPort Multi-Stream Transport (aka
DP-MST) support, print information of active connections for each device
of a display audio pin widget.

Example output with the patch with two monitors connected to a DP-MST hub:

Devices: 4
     Dev 00: PD = 0, ELDV = 0, IA = 0, Connections [ 0x03* 0x05 0x07 0x09 ]
     Dev 01: PD = 1, ELDV = 1, IA = 0, Connections [ 0x03* 0x05 0x07 0x09 ]
    *Dev 02: PD = 1, ELDV = 1, IA = 0, Connections [ 0x03 0x05* 0x07 0x09 ]
     Dev 03: PD = 0, ELDV = 0, IA = 0, Connections [ 0x03* 0x05 0x07 0x09 ]
Connection: 4
     0x03 0x05* 0x07 0x09

Format of existing "Connection:" entry is left intact to keep
compatibility.

Signed-off-by: Kai Vehmanen <kai.vehmanen@linux.intel.com>
Link: https://lore.kernel.org/r/20201208185736.2877541-1-kai.vehmanen@linux.intel.com


Signed-off-by: Takashi Iwai <tiwai@suse.de>