dt-bindings: pinctr: pinctrl-zynq: Fix compatible string

Compatible string doesn't really match with compatible string listed in the
driver itself. While binding was converted from txt to yaml
xlnx,zynq-pinctrl was listed as compatible string but example was using
xlnx,pinctrl-zynq and also this string is used in all DTSes.
xlnx,zynq-pinctrl is used only in dt binding and not present in any DT
which is stable for quite a long time that's why use old compatible string
and update binding document instead of starting to use unused compatible
string.

Fixes: 153df45acda0 ("dt-bindings: pinctrl: pinctrl-zynq: Convert to yaml")
Signed-off-by: Michal Simek <[e-mail]>
Acked-by: Conor Dooley <[e-mail]>
Link: https://lore.kernel.org/r/c130[e-mail]
Signed-off-by: Linus Walleij <[e-mail]>

Documentation/devicetree/bindings/pinctrl/xlnx,zynq-pinctrl.yaml Documentation/devicetree/bindings/pinctrl/xlnx,pinctrl-zynq.yaml

···
 # SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause
 %YAML 1.2
 ---
-$id: http://devicetree.org/schemas/pinctrl/xlnx,zynq-pinctrl.yaml#
+$id: http://devicetree.org/schemas/pinctrl/xlnx,pinctrl-zynq.yaml#
 $schema: http://devicetree.org/meta-schemas/core.yaml#
 
 title: Xilinx Zynq Pinctrl
···
 
 properties:
   compatible:
-    const: xlnx,zynq-pinctrl
+    const: xlnx,pinctrl-zynq
 
   reg:
     description: Specifies the base address and size of the SLCR space.
···
   - |
     #include <dt-bindings/pinctrl/pinctrl-zynq.h>
     pinctrl0: pinctrl@700 {
-       compatible = "xlnx,zynq-pinctrl";
+       compatible = "xlnx,pinctrl-zynq";
        reg = <0x700 0x200>;
        syscon = <&slcr>;