PCI: qcom: Remove unnecessary pipe_clk handling

PCIe PHY drivers (both QMP and PCIe2) already do clk_prepare_enable() /
clk_prepare_disable() pipe_clk. Remove extra calls to enable/disable
this clock from the PCIe driver, so that the PHY driver can manage the
clock on its own.

[bhelgaas: rebase on Robert Marko's DBI cleanup:
https://lore.kernel.org/r/20220623155004.688090-2-robimarko@gmail.com]
Link: https://lore.kernel.org/r/20220608105238.2973600-5-dmitry.baryshkov@linaro.org


Tested-by: Johan Hovold <johan+linaro@kernel.org>
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Reviewed-by: Johan Hovold <johan+linaro@kernel.org>
Reviewed-by: Stephen Boyd <sboyd@kernel.org>
Acked-by: Stanimir Varbanov <svarbanov@mm-sol.com>