dt-bindings: spi: add PIC64GX SPI/QSPI compatibility to MPFS SPI/QSPI bindings

PIC64GX SPI/QSPI are compatible with MPFS SPI/QSPI driver, we just use
fallback mechanism
Signed-off-by: Pierre-Henry Moussay <pierre-henry.moussay@microchip.com>
Link: https://patch.msgid.link/20240725121609.13101-5-pierre-henry.moussay@microchip.comSigned-off-by: Mark Brown <broonie@kernel.org>

Documentation/devicetree/bindings/spi/microchip,mpfs-spi.yaml

@@ -17,9 +17,14 @@ properties:
   compatible:
     oneOf:
       - items:
-          - const: microchip,mpfs-qspi
+          - enum:
+              - microchip,mpfs-qspi
+              - microchip,pic64gx-qspi
           - const: microchip,coreqspi-rtl-v2
       - const: microchip,coreqspi-rtl-v2 # FPGA QSPI
+      - items:
+          - const: microchip,pic64gx-spi
+          - const: microchip,mpfs-spi
       - const: microchip,mpfs-spi
 
   reg: