x86: dts: Add "m25p,fast-read" to SPI flash node

Except ICH7 SPI, all SPI flashes connected to ICH9 / Fast SPI should
have "m25p,fast-read" property present in their DT nodes.

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
diff --git a/arch/x86/dts/baytrail_som-db5800-som-6867.dts b/arch/x86/dts/baytrail_som-db5800-som-6867.dts
index a7dc03b..9c9b573 100644
--- a/arch/x86/dts/baytrail_som-db5800-som-6867.dts
+++ b/arch/x86/dts/baytrail_som-db5800-som-6867.dts
@@ -200,6 +200,7 @@
 					#address-cells = <1>;
 					#size-cells = <1>;
 					reg = <0>;
+					m25p,fast-read;
 					compatible = "macronix,mx25l6405d",
 						"jedec,spi-nor";
 					memory-map = <0xff800000 0x00800000>;