dt-bindings: soc: qcom: Support GLINK intents

Virtual GLINK channels may know what throughput to expect from a
remoteproc. An intent advertises to the remoteproc this channel is
ready to receive data. Allow a channel to define the size and amount of
intents to be prequeued.

Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Chris Lew <clew@codeaurora.org>
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>