remoteproc: qcom: Introduce Hexagon V5 based WCSS driver

IPQ8074 has an integrated Hexagon dsp core q6v5 and a wireless lan
(Lithium) IP. An mdt type single image format is used for the
firmware. So the mdt_load function can be directly used to load
the firmware. Also add the relevant resets required for this core.

Acked-by: Rob Herring <robh@kernel.org> (bindings)
Signed-off-by: Sricharan R <sricharan@codeaurora.org>
[bjorn: Rewrote as a separate driver, intead of extending q6v5_pil.c]
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>