dt-bindings: power: add R8A77970 SYSC power domain definitions

Add macros usable by the device tree sources to reference R8A77970 SYSC
power domains by index.

Based on the original (and large) patch by Daisuke Matsushita
<daisuke.matsushita.ns@hitachi.com>.
Signed-off-by: Vladimir Barinov <vladimir.barinov@cogentembedded.com>
Signed-off-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>

include/dt-bindings/power/r8a77970-sysc.h

+/*
+ * Copyright (C) 2017 Cogent Embedded Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+#ifndef __DT_BINDINGS_POWER_R8A77970_SYSC_H__
+#define __DT_BINDINGS_POWER_R8A77970_SYSC_H__
+
+/*
+ * These power domain indices match the numbers of the interrupt bits
+ * representing the power areas in the various Interrupt Registers
+ * (e.g. SYSCISR, Interrupt Status Register)
+ */
+
+#define R8A77970_PD_CA53_CPU0		 5
+#define R8A77970_PD_CA53_CPU1		 6
+#define R8A77970_PD_CR7			13
+#define R8A77970_PD_CA53_SCU		21
+#define R8A77970_PD_A2IR0		23
+#define R8A77970_PD_A3IR			24
+#define R8A77970_PD_A2IR1		27
+#define R8A77970_PD_A2IR2		28
+#define R8A77970_PD_A2IR3		29
+#define R8A77970_PD_A2SC0		30
+#define R8A77970_PD_A2SC1		31
+
+/* Always-on power area */
+#define R8A77970_PD_ALWAYS_ON		32
+
+#endif /* __DT_BINDINGS_POWER_R8A77970_SYSC_H__ */