remoteproc: qcom: Initialize and enable proxy and active clocks.

Certain clocks need voting by rproc on behalf of hexagon only during
restart operation but certain clocks need to be voted till hexagon is
up, these clocks are identified as proxy and active clocks respectively.
This patch provide interface to initialize, enable and disable proxy and
active clocks separately.

Signed-off-by: Avaneesh Kumar Dwivedi <akdwived@codeaurora.org>
[bjorn: dropped disable of proxy clocks on stop]
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>