phy: cadence: Sierra: Add PCIe + SGMII PHY multilink configuration

Add register sequences for PCIe + SGMII PHY multilink configuration.
This has been validated on TI J7 platforms.

Signed-off-by: Swapnil Jakhade <sjakhade@cadence.com>
Reviewed-by: Roger Quadros <rogerq@kernel.org>
Link: https://lore.kernel.org/r/20230403085644.10187-1-sjakhade@cadence.com


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