MAINTAINERS: update gpio-zynq.yaml reference

Changeset 45ca1607 ("dt-bindings: gpio: zynq: convert bindings to YAML")
renamed: Documentation/devicetree/bindings/gpio/gpio-zynq.txt
to: Documentation/devicetree/bindings/gpio/gpio-zynq.yaml.

Update its cross-reference accordingly.

Fixes: 45ca1607 ("dt-bindings: gpio: zynq: convert bindings to YAML")
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>

MAINTAINERS

@@ -20323,7 +20323,7 @@ R:	Srinivas Neeli <srinivas.neeli@xilinx.com>
 R:	Michal Simek <michal.simek@xilinx.com>
 S:	Maintained
 F:	Documentation/devicetree/bindings/gpio/gpio-xilinx.txt
-F:	Documentation/devicetree/bindings/gpio/gpio-zynq.txt
+F:	Documentation/devicetree/bindings/gpio/gpio-zynq.yaml
 F:	drivers/gpio/gpio-xilinx.c
 F:	drivers/gpio/gpio-zynq.c