arm64: dts: qcom: sdm845: use dispcc AHB clock for mdss node

It was noticed that on sdm845 after an MDSS suspend/resume cycle the
driver can not read HW_REV registers properly (they will return 0
instead). Chaning the "iface" clock from <&gcc GCC_DISP_AHB_CLK> to
<&dispcc DISP_CC_MDSS_AHB_CLK> fixes the issue.

Fixes: 08c2a076

 ("arm64: dts: qcom: sdm845: Add dpu to sdm845 dts file")
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Link: https://lore.kernel.org/r/20220531124735.1165582-1-dmitry.baryshkov@linaro.org