arm64: dts: ti: k3-am642-{evm,sk}: add ti,min-output-impedance

arm64: dts: ti: k3-am642-{evm,sk}: add ti,min-output-impedance

The default impedance for the MAC I/O lines from the DP83867 Ethernet PHY
is 50 Ohm. Based on the board PCB traces, this impedance is relatively
higher than expected, resulting in CRC errors for packets being transmitted
and received. Hence, add the "ti,min-output-impedance" device-tree property
to set the impedance to its lowest possible value of 35 Ohm as described in
the DP83867 Datasheet [0].

[0]: https://www.ti.com/lit/ds/symlink/dp83867e.pdf

Signed-off-by: Siddharth Vadapalli <s-vadapalli@ti.com>
Link: https://patch.msgid.link/20260223105448.1110428-2-s-vadapalli@ti.com
Signed-off-by: Vignesh Raghavendra <vigneshr@ti.com>