net: ti: icssg-prueth: am65x SR2.0 add 10M full duplex support

net: ti: icssg-prueth: am65x SR2.0 add 10M full duplex support

For AM65x SR2.0 it's required to enable IEP1 in raw 64bit mode which is
used by PRU FW to monitor the link and apply w/a for 10M link issue.
Note. No public errata available yet.

Without this w/a the PRU FW will stuck if link state changes under TX
traffic pressure.

Hence, add support for 10M full duplex for AM65x SR2.0:
 - add new IEP API to enable IEP, but without PTP support
 - add pdata quirk_10m_link_issue to enable 10M link issue w/a.

Signed-off-by: Grygorii Strashko <grygorii.strashko@ti.com>
Signed-off-by: Vignesh Raghavendra <vigneshr@ti.com>
Reviewed-by: Roger Quadros <rogerq@kernel.org>
Reviewed-by: Simon Horman <horms@kernel.org>
Reviewed-by: Jacob Keller <jacob.e.keller@intel.com>
Signed-off-by: MD Danish Anwar <danishanwar@ti.com>
Signed-off-by: David S. Miller <davem@davemloft.net>