clk: qcom: gpucc: Enable safe config and HW_CTL mode for gmu_clk_src

Enable the HW_CTL bit on RCGs in order to safely reconfigure and
update the RCG in the event that it's enabled from some other
hardware signal.

Change-Id: I4eb6b79be808dc8d5bb5fcaa5ee76f7501970c97
Signed-off-by: David Dai <daidavid1@codeaurora.org>