ARM: dts: at91: sama7g5: Add QSPI nodes

sama7g5 embedds 2 instances of QSPI controller:
1/ OSPI0 Supporting Up to 200 MHz DDR. Octal, TwinQuad, Hyperflash
   and OctaFlash Protocols Supported.
2/ QSPI1 Supporting Up to 90 MHz DDR/133 MHz SDR.

Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Signed-off-by: Nicolas Ferre <nicolas.ferre@microchip.com>
Link: https://lore.kernel.org/r/20211209123643.341892-1-tudor.ambarus@microchip.com