riscv: dts: microchip: move timebase-frequency to mpfs.dtsi

The timebase-frequency on PolarFire SoC is not set by an oscillator on
the board, but rather by an internal divider, so move the property to
mpfs.dtsi.

This looks to be copy-pasta from the SiFive Unleashed as the comments
in both places were almost identical. In the Unleashed's case this looks
to actually be valid, as the clock is provided by a crystal on the PCB.

Signed-off-by: Conor Dooley <[e-mail]>
---
CC: Conor Dooley <[e-mail]>
CC: Daire McNamara <[e-mail]>
CC: Rob Herring <[e-mail]>
CC: Krzysztof Kozlowski <[e-mail]>
CC: Paul Walmsley <[e-mail]>
CC: Palmer Dabbelt <[e-mail]>
CC: [e-mail]
CC: [e-mail]

arch/riscv/boot/dts/microchip/mpfs-icicle-kit.dts

···
 #include <dt-bindings/gpio/gpio.h>
 #include <dt-bindings/leds/common.h>
 
-/* Clock frequency (in Hz) of the rtcclk */
-#define RTCCLK_FREQ		1000000
-
 / {
 	model = "Microchip PolarFire-SoC Icicle Kit";
 	compatible = "microchip,mpfs-icicle-reference-rtlv2210", "microchip,mpfs-icicle-kit",
···
 
 	chosen {
 		stdout-path = "serial1:115200n8";
-	};
-
-	cpus {
-		timebase-frequency = <RTCCLK_FREQ>;
 	};
 
 	leds {

arch/riscv/boot/dts/microchip/mpfs-m100pfsevp.dts

···
 #include "mpfs.dtsi"
 #include "mpfs-m100pfs-fabric.dtsi"
 
-/* Clock frequency (in Hz) of the rtcclk */
-#define MTIMER_FREQ	1000000
-
 / {
 	model = "Aries Embedded M100PFEVPS";
 	compatible = "aries,m100pfsevp", "microchip,mpfs";
···
 
 	chosen {
 		stdout-path = "serial1:115200n8";
-	};
-
-	cpus {
-		timebase-frequency = <MTIMER_FREQ>;
 	};
 
 	ddrc_cache_lo: memory@80000000 {

arch/riscv/boot/dts/microchip/mpfs-polarberry.dts

···
 #include "mpfs.dtsi"
 #include "mpfs-polarberry-fabric.dtsi"
 
-/* Clock frequency (in Hz) of the rtcclk */
-#define MTIMER_FREQ	1000000
-
 / {
 	model = "Sundance PolarBerry";
 	compatible = "sundance,polarberry", "microchip,mpfs";
···
 
 	chosen {
 		stdout-path = "serial0:115200n8";
-	};
-
-	cpus {
-		timebase-frequency = <MTIMER_FREQ>;
 	};
 
 	ddrc_cache_lo: memory@80000000 {

arch/riscv/boot/dts/microchip/mpfs-sev-kit.dts

···
 #include "mpfs.dtsi"
 #include "mpfs-sev-kit-fabric.dtsi"
 
-/* Clock frequency (in Hz) of the rtcclk */
-#define MTIMER_FREQ		1000000
-
 / {
 	#address-cells = <2>;
 	#size-cells = <2>;
···
 
 	chosen {
 		stdout-path = "serial1:115200n8";
-	};
-
-	cpus {
-		timebase-frequency = <MTIMER_FREQ>;
 	};
 
 	reserved-memory {

arch/riscv/boot/dts/microchip/mpfs-tysom-m.dts

···
 #include "mpfs.dtsi"
 #include "mpfs-tysom-m-fabric.dtsi"
 
-/* Clock frequency (in Hz) of the rtcclk */
-#define MTIMER_FREQ		1000000
-
 / {
 	model = "Aldec TySOM-M-MPFS250T-REV2";
 	compatible = "aldec,tysom-m-mpfs250t-rev2", "microchip,mpfs";
···
 
 	chosen {
 		stdout-path = "serial1:115200n8";
-	};
-
-	cpus {
-		timebase-frequency = <MTIMER_FREQ>;
 	};
 
 	ddrc_cache_lo: memory@80000000 {

arch/riscv/boot/dts/microchip/mpfs.dtsi

···
 	cpus {
 		#address-cells = <1>;
 		#size-cells = <0>;
+		timebase-frequency = <1000000>;
 
 		cpu0: cpu@0 {
 			compatible = "sifive,e51", "sifive,rocket0", "riscv";