ALSA: Move some headers to local directories from include/sound

This is a bit clean up of public sound header directory.
Some header files in include/sound aren't really necessary to be
located there but can be moved to their local directories gracefully.

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

sound/pci/ymfpci/ymfpci.c

@@ -24,7 +24,7 @@
 #include <linux/time.h>
 #include <linux/module.h>
 #include <sound/core.h>
-#include <sound/ymfpci.h>
+#include "ymfpci.h"
 #include <sound/mpu401.h>
 #include <sound/opl3.h>
 #include <sound/initval.h>