net: ethernet: ti: am65-cpts: reset pps genf adj settings on enable

The CPTS PPS GENf adjustment settings are invalid after it has been
disabled for a while, so reset them.

Fixes: eb9233ce

 ("net: ethernet: ti: am65-cpts: adjust pps following ptp changes")
Signed-off-by: Grygorii Strashko <grygorii.strashko@ti.com>
Signed-off-by: Siddharth Vadapalli <s-vadapalli@ti.com>
Reviewed-by: Roger Quadros <rogerq@kernel.org>
Reviewed-by: Michal Swiatkowski <michal.swiatkowski@linux.intel.com>
Link: https://lore.kernel.org/r/20230316095232.2002680-1-s-vadapalli@ti.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>