dt-bindings: net: micrel: Revert latency support and timestamping check

Revert latency support from binding.
Based on the discussion[1], the DT is the wrong place to have the
lantecies for the PHY.

[1] https://lkml.org/lkml/2022/3/4/325



Fixes: 2358dd3f ("dt-bindings: net: micrel: Configure latency values and timestamping check for LAN8814 phy")
Signed-off-by: Horatiu Vultur <horatiu.vultur@microchip.com>
Signed-off-by: David S. Miller <davem@davemloft.net>