ALSA: hdsp: Add missing inclusion of linux/vmalloc.h

Reported-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
diff --git a/sound/pci/rme9652/hdsp.c b/sound/pci/rme9652/hdsp.c
index b8ddbb1..0f82bb5 100644
--- a/sound/pci/rme9652/hdsp.c
+++ b/sound/pci/rme9652/hdsp.c
@@ -28,6 +28,7 @@
 #include <linux/firmware.h>
 #include <linux/module.h>
 #include <linux/math64.h>
+#include <linux/vmalloc.h>
 
 #include <sound/core.h>
 #include <sound/control.h>