net: ethernet: ti: am65-cpsw-nuss: Fix rx_filter value for PTP support

net: ethernet: ti: am65-cpsw-nuss: Fix rx_filter value for PTP support

The "rx_filter" member of "hwtstamp_config" structure is an enum field and
does not support bitwise OR combination of multiple filter values. It
causes error while linuxptp application tries to match rx filter version.
Fix this by storing the requested filter type in a new port field.

Fixes: 97248adb5a3b ("net: ti: am65-cpsw: Update hw timestamping filter for PTPv1 RX packets")
Signed-off-by: Chintan Vankar <c-vankar@ti.com>
Link: https://patch.msgid.link/20260310160940.109822-1-c-vankar@ti.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>