Boards like phyBOARD-WEGA-rdk do not have SPI Flash.
The compatible string was not updated when merging all phytec
am335x SOMs to one board file.
Updating this now.
Signed-off-by: Teresa Gámez <t.gamez@phytec.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>