dt-bindings: phy: amlogic,meson-axg-mipi-pcie-analog: drop text about parent syscon and drop example

Since this bindings is referred from amlogic,meson-gx-hhi-sysctrl.yaml, drop the now
useless description about the parent node and also drop the unnecessary example.

Acked-by: Conor Dooley <[e-mail]>
Signed-off-by: Neil Armstrong <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Vinod Koul <[e-mail]>

Documentation/devicetree/bindings/phy/amlogic,meson-axg-mipi-pcie-analog.yaml

···
 maintainers:
   - Remi Pommarel <[e-mail]>
 
-description: |+
-  The Everything-Else Power Domains node should be the child of a syscon
-  node with the required property:
-
-  - compatible: Should be the following:
-                "amlogic,meson-gx-hhi-sysctrl", "simple-mfd", "syscon"
-
-  Refer to the bindings described in
-  Documentation/devicetree/bindings/mfd/syscon.yaml
-
 properties:
   compatible:
     const: amlogic,axg-mipi-pcie-analog-phy
···
   - "#phy-cells"
 
 additionalProperties: false
-
-examples:
-  - |
-    mpphy: phy {
-          compatible = "amlogic,axg-mipi-pcie-analog-phy";
-          #phy-cells = <0>;
-    };