Some boards form the MangoPi family (MQ\MQ-Dual\MQ-R) may have
an optional SPI flash that connects to the SPI0 controller.

This controller is the same for R329/D1/R528/T113s SoCs and
should be supported by the sun50i-r329-spi driver.

So let's add its DT nodes.
Signed-off-by: Maksim Kiselev <bigunclemax@gmail.com>
Acked-by: Conor Dooley <conor.dooley@microchip.com>
Reviewed-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Jernej Skrabec <jernej.skrabec@gmail.com>
Link: https://lore.kernel.org/r/20230510081121.3463710-6-bigunclemax@gmail.comSigned-off-by: Jernej Skrabec <jernej.skrabec@gmail.com>