realtek: add PLL DT binding includes

Add some constants for sharing between DT and drivers.

Signed-off-by: Markus Stockhausen <markus.stockhausen@gmx.de>

target/linux/realtek/files-5.10/include/dt-bindings/clock/rtl83xx-clk.h

@@ -0,0 +1,15 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Copyright (C) 2022 Markus Stockhausen
+ *
+ * RTL83XX clock indices
+ */
+#ifndef __DT_BINDINGS_CLOCK_RTL83XX_H
+#define __DT_BINDINGS_CLOCK_RTL83XX_H
+
+#define CLK_CPU		0
+#define CLK_MEM		1
+#define CLK_LXB		2
+#define CLK_COUNT	3
+
+#endif /* __DT_BINDINGS_CLOCK_RTL83XX_H */