ALSA: hda - A new flag to enforce prefix to each pin

This is a preliminary patch for a smooth multi-codec support, and it
introduces a new flag, force_pin_prefix, to struct hda_codec.
This flag is used to force to add the pin location prefix to each
input pin.  For example, when there is only one microphone pin,
usually the auto-parser assigns the string "Mic".  With this flag on,
it'll be like "Front Mic".  Also, the creation of "Master" or "PCM"
playback volume for a single pin is suppressed, too.

Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=195305
Signed-off-by: Takashi Iwai <tiwai@suse.de>
diff --git a/sound/pci/hda/hda_codec.h b/sound/pci/hda/hda_codec.h
index f17f252..d6fb2d5 100644
--- a/sound/pci/hda/hda_codec.h
+++ b/sound/pci/hda/hda_codec.h
@@ -256,6 +256,7 @@ struct hda_codec {
 	unsigned int dump_coef:1; /* dump processing coefs in codec proc file */
 	unsigned int power_save_node:1; /* advanced PM for each widget */
 	unsigned int auto_runtime_pm:1; /* enable automatic codec runtime pm */
+	unsigned int force_pin_prefix:1; /* Add location prefix */
 #ifdef CONFIG_PM
 	unsigned long power_on_acct;
 	unsigned long power_off_acct;