Drop the unused and incomplete runtime PM implementation, which was
only used by USB PHYs before splitting the QMP driver.

Note that the runtime PM was never disabled (and state restored) on
driver unbind.

This effectively reverts commit ac0d2399 ("phy: qcom-qmp: Add
support for runtime PM").
Signed-off-by: Johan Hovold <johan+linaro@kernel.org>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Link: https://lore.kernel.org/r/20220907110728.19092-8-johan+linaro@kernel.orgSigned-off-by: Vinod Koul <vkoul@kernel.org>