phy: qcom: edp: Postpone clk_set_rate until the PLL is up

phy: qcom: edp: Postpone clk_set_rate until the PLL is up

When the platform was booted with the involved clocks enabled the
clk_set_rate() of the link and pixel clocks will perculate to the
children, which will fail to update because the PHY driver has just shut
down the PLL.

Postpone the clock rate updates until the PLL is back online to avoid
reconfiguring the clocks while the PLL is not ticking.

Fixes: f199223cb490 ("phy: qcom: Introduce new eDP PHY driver")
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Link: https://lore.kernel.org/r/20220805154432.546740-1-bjorn.andersson@linaro.org
Signed-off-by: Vinod Koul <vkoul@kernel.org>