phy: qcom: sgmii-eth: move PCS registers to separate header

Follow the example of the rest of the QMP PHY drivers and move SGMII PCS
registers to a separate header file.

Cc: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Link: https://lore.kernel.org/r/20240126-phy-qmp-merge-common-v2-8-a463d0b57836@linaro.org
Signed-off-by: Vinod Koul <vkoul@kernel.org>

phy: qcom: sgmii-eth: use existing register definitions

The Qualcomm SGMII SerDes PHY is a QMP PHY. As such, it uses standard
registers for QSERDES COM/RX/TX regions. Use register defines from the
existing headers.

Cc: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Link: https://lore.kernel.org/r/20240126-phy-qmp-merge-common-v2-7-a463d0b57836@linaro.org
Signed-off-by: Vinod Koul <vkoul@kernel.org>

phy: qcom: add the SGMII SerDes PHY driver

Implement support for the SGMII/SerDes PHY present on various Qualcomm
platforms.

Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Link: https://lore.kernel.org/r/20230619091336.194914-4-brgl@bgdev.pl
Signed-off-by: Vinod Koul <vkoul@kernel.org>