ARM: dts: at91: usb_a9263: fix GPIO for Dataflash chip select

ARM: dts: at91: usb_a9263: fix GPIO for Dataflash chip select

[ Upstream commit 67ba341e57ab158423818ed33bfa1c40eb0e5e7e ]

Dataflash did not work on my board. After checking schematics and using
the proper GPIO, it works now. Also, make it active low to avoid:

flash@0 enforce active low on GPIO handle

Fixes: 2432d201468d ("ARM: at91: dt: usb-a9263: add dataflash support")
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Link: https://lore.kernel.org/r/20250404112742.67416-2-wsa+renesas@sang-engineering.com
Signed-off-by: Claudiu Beznea <claudiu.beznea@tuxon.dev>
Signed-off-by: Sasha Levin <sashal@kernel.org>