video/rockchip: rga2: Ion can be used below kernel4.4.

Signed-off-by: Yu Qiaowei <cerf.yu@rock-chips.com>
Change-Id: Ie9da1dfcd8682875763d401bc0c5d874ad98b870

Author: Yu Qiaowei

drivers/video/rockchip/rga2/rga2_drv.c

@@ -54,7 +54,7 @@
 #include "rga2_mmu_info.h"
 #include "RGA2_API.h"
 
-#if defined(CONFIG_ION_ROCKCHIP)
+#if IS_ENABLED(CONFIG_ION_ROCKCHIP) && (LINUX_VERSION_CODE < KERNEL_VERSION(4, 4, 0))
 #include <linux/rockchip_ion.h>
 #endif