staging: android: ashmem: add missing include

Include <linux/types.h> into ashmem.h to ensure referenced types are defined

Signed-off-by: Rom Lemarchand <romlem@android.com>
Change-Id: If82d92caa6c148ab2182a681637fc8e17c44346d
diff --git a/include/linux/ashmem.h b/include/linux/ashmem.h
index 25a190e..c01a141 100644
--- a/include/linux/ashmem.h
+++ b/include/linux/ashmem.h
@@ -14,6 +14,7 @@
 
 #include <linux/limits.h>
 #include <linux/ioctl.h>
+#include <linux/types.h>
 
 #define ASHMEM_NAME_LEN		256