rockchip: rename miniarm to tinker board

Miniarm is the internal project code. Now it is officially named Tinker board.
So rename it.

Signed-off-by: Eddie Cai <eddie.cai@rock-chips.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
diff --git a/board/rockchip/tinker_rk3288/Kconfig b/board/rockchip/tinker_rk3288/Kconfig
new file mode 100644
index 0000000..bca6c37
--- /dev/null
+++ b/board/rockchip/tinker_rk3288/Kconfig
@@ -0,0 +1,15 @@
+if TARGET_TINKER_RK3288
+
+config SYS_BOARD
+	default "tinker_rk3288"
+
+config SYS_VENDOR
+	default "rockchip"
+
+config SYS_CONFIG_NAME
+	default "tinker_rk3288"
+
+config BOARD_SPECIFIC_OPTIONS # dummy
+	def_bool y
+
+endif