phy: qcom: Add M31 based eUSB2 PHY driver

phy: qcom: Add M31 based eUSB2 PHY driver

SM8750 utilizes an eUSB2 PHY from M31. Add the initialization
sequences to bring it out of reset and into an operational state. This
differs to the M31 USB driver, in that the M31 eUSB2 driver will
require a connection to an eUSB2 repeater. This PHY driver will handle
the initialization of the associated eUSB2 repeater when required.

Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>
Signed-off-by: Wesley Cheng <quic_wcheng@quicinc.com>
Signed-off-by: Melody Olvera <melody.olvera@oss.qualcomm.com>
Link: https://lore.kernel.org/r/20250527-sm8750_usb_master-v6-6-d58de3b41d34@oss.qualcomm.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>