dt-bindings: fpga: altera: Convert bridge bindings to yaml

Convert Altera's bridges to yaml with using fpga-bridge.yaml.

Signed-off-by: Michal Simek <michal.simek@amd.com>
Reviewed-by: Xu Yilun <yilun.xu@intel.com>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://lore.kernel.org/r/07d646a6d82cc21b100e45ced7cae3ef05faa2cc.1704807147.git.michal.simek@amd.com
Signed-off-by: Rob Herring <robh@kernel.org>