ALSA: hda - Add missing inclusion of linux/export.h

This is needed newly since 3.2...
Signed-off-by: Takashi Iwai <tiwai@suse.de>

sound/core/ctljack.c

@@ -10,6 +10,7 @@
  */
 
 #include <linux/kernel.h>
+#include <linux/export.h>
 #include <sound/core.h>
 #include <sound/control.h>
 

sound/pci/hda/hda_jack.c

@@ -11,6 +11,7 @@
 
 #include <linux/init.h>
 #include <linux/slab.h>
+#include <linux/export.h>
 #include <sound/core.h>
 #include <sound/control.h>
 #include <sound/jack.h>