dt-bindings: hwmon: Fix incorrect $id paths

Fix the path warnings in the adi,axi-fan-control and adt7475 bindings:

Documentation/devicetree/bindings/hwmon/adt7475.yaml: $id:
  relative path/filename doesn't match actual path or filename
  expected: http://devicetree.org/schemas/hwmon/adt7475.yaml#
Documentation/devicetree/bindings/hwmon/adi,axi-fan-control.yaml: $id:
  relative path/filename doesn't match actual path or filename
  expected: http://devicetree.org/schemas/hwmon/adi,axi-fan-control.yaml#

Cc: Jean Delvare <jdelvare@suse.com>
Cc: linux-hwmon@vger.kernel.org
Acked-by: Guenter Roeck <linux@roeck-us.net>
Acked-by: Nuno Sá <nuno.sa@analog.com>
Signed-off-by: Rob Herring <robh@kernel.org>

Documentation/devicetree/bindings/hwmon/adi,axi-fan-control.yaml

@@ -2,7 +2,7 @@
 # Copyright 2019 Analog Devices Inc.
 %YAML 1.2
 ---
-$id: http://devicetree.org/schemas/bindings/hwmon/adi,axi-fan-control.yaml#
+$id: http://devicetree.org/schemas/hwmon/adi,axi-fan-control.yaml#
 $schema: http://devicetree.org/meta-schemas/core.yaml#
 
 title: Analog Devices AXI FAN Control Device Tree Bindings

Documentation/devicetree/bindings/hwmon/adt7475.yaml

 # SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
 %YAML 1.2
 ---
-$id: http://devicetree.org/schemas/adt7475.yaml#
+$id: http://devicetree.org/schemas/hwmon/adt7475.yaml#
 $schema: http://devicetree.org/meta-schemas/core.yaml#
 
 title: ADT7475 hwmon sensor