rockchip: configs: move env offset to common header

To reduce redundant code.

Signed-off-by: Jacob Chen <jacob2.chen@rock-chips.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
diff --git a/include/configs/rockchip-common.h b/include/configs/rockchip-common.h
index 9e71b3f..fd930c1 100644
--- a/include/configs/rockchip-common.h
+++ b/include/configs/rockchip-common.h
@@ -31,4 +31,18 @@
 
 #endif
 
+#ifdef CONFIG_ROCKCHIP_SPL_BACK_TO_BROM
+/* SPL @ 32k for 34k
+ * u-boot directly after @ 68k for 400k or so
+ * ENV @ 992k
+ */
+#define CONFIG_ENV_OFFSET ((1024-32) * 1024)
+#else
+/* SPL @ 32k for ~36k
+ * ENV @ 96k
+ * u-boot @ 128K
+ */
+#define CONFIG_ENV_OFFSET (96 * 1024)
+#endif
+
 #endif /* _ROCKCHIP_COMMON_H_ */