net: ethernet: renesas: rcar_gen4_ptp: Remove different memory layout

net: ethernet: renesas: rcar_gen4_ptp: Remove different memory layout

When upstreaming the Gen4 PTP support for R-Car S4 the possibility for
different memory layouts on other Gen4 SoCs was build in. It turns out
this is not needed and instead needlessly makes the driver harder to
read, remove the support code that would have allowed different memory
layouts.

This change only deals with the public functions used by other drivers,
follow up work will clean up the rcar_gen4_ptp internals.

Signed-off-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/20250908154426.3062861-2-niklas.soderlund+renesas@ragnatech.se
Signed-off-by: Jakub Kicinski <kuba@kernel.org>