dt-bindings: net: snps,dwmac: Fix snps,reset-delays-us dependency

dt-bindings: net: snps,dwmac: Fix snps,reset-delays-us dependency

The schema had snps,reset-delay-us as dependent on snps,reset-gpio. The
actual property is called snps,reset-delays-us, so fix this to catch any
devicetree defining snsps,reset-delays-us without snps,reset-gpio.

Fixes: 7db3545aef5f ("dt-bindings: net: stmmac: Convert the binding to a schemas")
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Andrew Halaney <ahalaney@redhat.com>
Link: https://lore.kernel.org/r/20230214171505.224602-1-ahalaney@redhat.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>