dt-bindings: qcom: Add IPQ8074 bindings

This patch adds the IPQ8074 and related boards to the QCOM bindings.

Signed-off-by: Varadarajan Narayanan <varada@codeaurora.org>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Andy Gross <andy.gross@linaro.org>