ARM: dts: qcom: apq8064: rename DSI PHY iface clock

Follow the usual scheme and use name 'iface' rather than 'iface_clk' for
the interface clock. The DSI PHY driver can cope with both of them, so
there is no breakage.

Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Link: https://lore.kernel.org/r/20220706145412.1566011-4-dmitry.baryshkov@linaro.org