[ALSA] hda-codec - Make the mixer capability check more robust

In some cases, mixer elements return -EINVAL because it couldn't
obtain proper amp_cap bits.  The patch improves the robustness,
trying the amp_cap query again in such a case.
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Jaroslav Kysela <perex@suse.cz>

sound/pci/hda/hda_codec.c

@@ -707,6 +707,7 @@ static u32 query_amp_caps(struct hda_codec *codec, hda_nid_t nid, int direction)
 						    direction == HDA_OUTPUT ?
 						    AC_PAR_AMP_OUT_CAP :
 						    AC_PAR_AMP_IN_CAP);
+		if (info->amp_caps)
 			info->status |= INFO_AMP_CAPS;
 	}
 	return info->amp_caps;