spi: Add resets to the PL022 bindings

Some PL022 implementations provide a reset line to the silicon
IP block, add a device tree property for this.

Cc: devicetree@vger.kernel.org
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/20211120011715.2630873-1-linus.walleij@linaro.org
Signed-off-by: Mark Brown <broonie@kernel.org>

Documentation/devicetree/bindings/spi/spi-pl022.yaml

@@ -72,6 +72,9 @@ properties:
       - const: rx
       - const: tx
 
+  resets:
+    maxItems: 1
+
 patternProperties:
   "^[a-zA-Z][a-zA-Z0-9,+\\-._]{0,63}@[0-9a-f]+$":
     type: object