dt-bindings: i2c: at91: Add SAMA7G5 compatible strings list

Add compatible strings list for SAMA7G5.

Signed-off-by: Sergiu Moga <sergiu.moga@microchip.com>
Signed-off-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20220310114553.184763-4-sergiu.moga@microchip.com