soc: rockchip: vendor storage: include rk_vendor_storage.h

Fix the following warning(s):
drivers/soc/rockchip/rk_vendor_storage.c:15:5: warning: no previous prototype for ‘rk_vendor_read’ [-Wmissing-prototypes]
drivers/soc/rockchip/rk_vendor_storage.c:23:5: warning: no previous prototype for ‘rk_vendor_write’ [-Wmissing-prototypes]
drivers/soc/rockchip/rk_vendor_storage.c:31:5: warning: no previous prototype for ‘rk_vendor_register’ [-Wmissing-prototypes]
drivers/soc/rockchip/rk_vendor_storage.c:42:6: warning: no previous prototype for ‘is_rk_vendor_ready’ [-Wmissing-prototype

Change-Id: Ia264c96adac27ff1e639532b7bdfde464f54e637
Signed-off-by: Yifeng Zhao <zyf@rock-chips.com>

drivers/soc/rockchip/rk_vendor_storage.c

@@ -8,6 +8,7 @@
  */
 
 #include <linux/kernel.h>
+#include <linux/soc/rockchip/rk_vendor_storage.h>
 
 int (*_vendor_read)(u32 id, void *pbuf, u32 size) = NULL;
 int (*_vendor_write)(u32 id, void *pbuf, u32 size) = NULL;