dt-bindings: mtd: spi-nor: Add reset-gpios property

SPI-NOR flashes have RESET pin which can be toggled using GPIO
controller, for those platforms reset-gpios property can be used to
reset the flash device.

Signed-off-by: Sai Krishna Potthuri <sai.krishna.potthuri@amd.com>
Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://lore.kernel.org/r/20220908064428.2962-2-sai.krishna.potthuri@amd.com

Documentation/devicetree/bindings/mtd/jedec,spi-nor.yaml

@@ -70,6 +70,12 @@ properties:
       be used on such systems, to denote the absence of a reliable reset
       mechanism.
 
+  reset-gpios:
+    description:
+      A GPIO line connected to the RESET (active low) signal of the device.
+      If "broken-flash-reset" is present then having this property does not
+      make any difference.
+
   partitions:
     type: object
 
@@ -88,6 +94,7 @@ unevaluatedProperties: false
 
 examples:
   - |
+    #include <dt-bindings/gpio/gpio.h>
     spi {
         #address-cells = <1>;
         #size-cells = <0>;
@@ -97,6 +104,7 @@ examples:
             reg = <0>;
             spi-max-frequency = <40000000>;
             m25p,fast-read;
+            reset-gpios = <&gpio 12 GPIO_ACTIVE_LOW>;
         };
     };
 ...