[ALSA] vx-driver - Fix PM support

Fix PM support on VX drivers (vxpocket and vx222).

Signed-off-by: Takashi Iwai <tiwai@suse.de>
diff --git a/include/sound/vx_core.h b/include/sound/vx_core.h
index 0a85c37..5fd6f33 100644
--- a/include/sound/vx_core.h
+++ b/include/sound/vx_core.h
@@ -347,6 +347,12 @@
 
 
 /*
+ * PM
+ */
+int snd_vx_suspend(struct vx_core *card, pm_message_t state);
+int snd_vx_resume(struct vx_core *card);
+
+/*
  * hardware constants
  */