phy: cadence: Sierra: Add support for skipping configuration

In some cases, a single SerDes instance can be shared between two different
processors, each using a separate link. In these cases, the SerDes
configuration is done in an earlier boot stage. Therefore, add support to
skip reconfiguring, if it is was already configured beforehand.

Signed-off-by: Aswath Govindraju <a-govindraju@ti.com>
Reviewed-by: Dan Carpenter <dan.carpenter@oracle.com>
Link: https://lore.kernel.org/r/20220128072642.29188-1-a-govindraju@ti.com


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