misc: lan966x_pci: Fix dtc warns 'missing or empty reg/ranges property'

dtc generates the following warnings when building the LAN966x device
tree overlay (lan966x_pci.dtso):
  Warning (simple_bus_reg): /fragment@0/__overlay__/pci-ep-bus@0/cpu_clk: missing or empty reg/ranges property
  Warning (simple_bus_reg): /fragment@0/__overlay__/pci-ep-bus@0/ddr_clk: missing or empty reg/ranges property
  Warning (simple_bus_reg): /fragment@0/__overlay__/pci-ep-bus@0/sys_clk: missing or empty reg/ranges property

Indeed, related nodes are under the pci-ep-bus (simple-bus) which is not
correct.

Put them outside this node.

Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Closes: https://lore.kernel.org/all/20241025110919.64b1cffb@canb.auug.org.au/
Fixes: 185686b ("misc: Add support for LAN966x PCI device")
Signed-off-by: Herve Codina <herve.codina@bootlin.com>
Reviewed-by: Rob Herring (Arm) <robh@kernel.org>
Link: https://lore.kernel.org/r/20241029084338.194942-2-herve.codina@bootlin.com
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>

Author: hcodina

drivers/misc/lan966x_pci.dtso

@@ -19,6 +19,24 @@
 			#address-cells = <3>;
 			#size-cells = <2>;
 
+			cpu_clk: clock-600000000 {
+				compatible = "fixed-clock";
+				#clock-cells = <0>;
+				clock-frequency = <600000000>;  /* CPU clock = 600MHz */
+			};
+
+			ddr_clk: clock-30000000 {
+				compatible = "fixed-clock";
+				#clock-cells = <0>;
+				clock-frequency = <30000000>;  /* Fabric clock = 30MHz */
+			};
+
+			sys_clk: clock-15625000 {
+				compatible = "fixed-clock";
+				#clock-cells = <0>;
+				clock-frequency = <15625000>;  /* System clock = 15.625MHz */
+			};
+
 			pci-ep-bus@0 {
 				compatible = "simple-bus";
 				#address-cells = <1>;
@@ -39,24 +57,6 @@
 					reg = <0xe00c0120 0x190>;
 				};
 
-				cpu_clk: cpu_clk {
-					compatible = "fixed-clock";
-					#clock-cells = <0>;
-					clock-frequency = <600000000>;  // CPU clock = 600MHz
-				};
-
-				ddr_clk: ddr_clk {
-					compatible = "fixed-clock";
-					#clock-cells = <0>;
-					clock-frequency = <30000000>;  // Fabric clock = 30MHz
-				};
-
-				sys_clk: sys_clk {
-					compatible = "fixed-clock";
-					#clock-cells = <0>;
-					clock-frequency = <15625000>;  // System clock = 15.625MHz
-				};
-
 				cpu_ctrl: syscon@e00c0000 {
 					compatible = "microchip,lan966x-cpu-syscon", "syscon";
 					reg = <0xe00c0000 0xa8>;