dt-bindings: net: Add Qualcomm ethqos binding

Add support for Qualcomm ethqos found in some SoCs like QCS404.

Signed-off-by: Vinod Koul <vkoul@kernel.org>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>