MIPS: CI20: Add second percpu timer for SMP.

1.Add a new TCU channel as the percpu timer of core1, this is to
  prepare for the subsequent SMP support. The newly added channel
  will not adversely affect the current single-core state.
2.Adjust the position of TCU node to make it consistent with the
  order in jz4780.dtsi file.

Tested-by: Nikolaus Schaller <hns@goldelico.com> # on CI20
Signed-off-by: 周琰杰 (Zhou Yanjie) <zhouyanjie@wanyeetech.com>
Acked-by: Paul Cercueil <paul@crapouillou.net>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

arch/mips/boot/dts/ingenic/ci20.dts

@@ -118,6 +118,20 @@ &cgu {
 	assigned-clock-rates = <48000000>;
 };
 
+&tcu {
+	/*
+	 * 750 kHz for the system timers and clocksource,
+	 * use channel #0 and #1 for the per cpu system timers,
+	 * and use channel #2 for the clocksource.
+	 *
+	 * 3000 kHz for the OST timer to provide a higher
+	 * precision clocksource.
+	 */
+	assigned-clocks = <&tcu TCU_CLK_TIMER0>, <&tcu TCU_CLK_TIMER1>,
+					  <&tcu TCU_CLK_TIMER2>, <&tcu TCU_CLK_OST>;
+	assigned-clock-rates = <750000>, <750000>, <750000>, <3000000>;
+};
+
 &mmc0 {
 	status = "okay";
 
@@ -522,13 +536,3 @@ pins_mmc1: mmc1 {
 		bias-disable;
 	};
 };
-
-&tcu {
-	/*
-	 * 750 kHz for the system timer and clocksource,
-	 * use channel #0 for the system timer, #1 for the clocksource.
-	 */
-	assigned-clocks = <&tcu TCU_CLK_TIMER0>, <&tcu TCU_CLK_TIMER1>,
-					  <&tcu TCU_CLK_OST>;
-	assigned-clock-rates = <750000>, <750000>, <3000000>;
-};