spi: dt-bindings: at91: Add sama7d65 compatible string

Add compatible string for sama7d65. Like sam9x60 and sam9x7, it requires
to bind to "atmel,at91rm9200-spi".
Group these three under the same enum, sorted alphanumerically, and
remove previously added item.

Signed-off-by: Nicolas Ferre <nicolas.ferre@microchip.com>
Acked-by: Rob Herring (Arm) <robh@kernel.org>
Link: https://patch.msgid.link/20240711165402.373634-1-nicolas.ferre@microchip.com
Signed-off-by: Mark Brown <broonie@kernel.org>