dt-bindings: fsl: fsl,imx7ulp-smc1: Allow clocks and clock-names

Allow clocks and clock-names to match existed dts file.

'hsrun_divcore' should be 'hsrun-divcore'. But use '_' to keep old dts back
compatible.

Fix below CHECK_DTBS warnings:
arch/arm/boot/dts/nxp/imx/imx7ulp-com.dtb: clock-controller@40410000 (fsl,imx7ulp-smc1): '#clock-cells', 'clock-names', 'clocks' do not match any of the regexes: '^pinctrl-[0-9]+$'
from schema $id: http://devicetree.org/schemas/arm/freescale/fsl,imx7ulp-pm.yaml#

Signed-off-by: Frank Li <[e-mail]>
Acked-by: Rob Herring (Arm) <[e-mail]>
Signed-off-by: Shawn Guo <[e-mail]>

Documentation/devicetree/bindings/arm/freescale/fsl,imx7ulp-pm.yaml

···
   reg:
     maxItems: 1
 
+  clocks:
+    maxItems: 2
+
+  clock-names:
+    items:
+      - const: divcore
+      - const: hsrun_divcore
+
 required:
   - compatible
   - reg