ALSA: hda: move hda_codec.h to include/sound

As suggested by Takashi, move this header file to make it easier
to include from e.g. the Intel Skylake driver in follow-up patches

Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

sound/pci/hda/hda_intel.c

@@ -63,7 +63,7 @@
 #include <linux/vgaarb.h>
 #include <linux/vga_switcheroo.h>
 #include <linux/firmware.h>
-#include "hda_codec.h"
+#include <sound/hda_codec.h>
 #include "hda_controller.h"
 #include "hda_intel.h"