arm: mvebu: solidrun-microsom: update SPI flash compatible

Add the "spi-flash" compatible string so that the generic sf_probe
driver can probe the SPI flash on the SolidRun SOM.

Signed-off-by: Baruch Siach <baruch@tkos.co.il>
Signed-off-by: Stefan Roese <sr@denx.de>
1 file changed