phy: qcom: qmp-usbc: drop has_pwrdn_delay handling

None of the PHYs supported by the USBC driver need power down delay.
Drop corresponding flag and code.

Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Link: https://lore.kernel.org/r/20240126-phy-qmp-merge-common-v2-6-a463d0b57836@linaro.org


Signed-off-by: Vinod Koul <vkoul@kernel.org>