arm64: dts: lx2160a: update fspi node

Flash mt35xu512aba connected to FlexSPI controller supports
1-1-8/1-8-8 protocol.
Added flag spi-rx-bus-width and spi-tx-bus-width with values as
8 and 8 respectively for both flashes connected at CS0 and CS1.
Signed-off-by: Yogesh Narayan Gaur <yogeshnarayan.gaur@nxp.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>

arch/arm64/boot/dts/freescale/fsl-lx2160a-rdb.dts

@@ -60,6 +60,8 @@ mt35xu512aba0: flash@0 {
 		m25p,fast-read;
 		spi-max-frequency = <50000000>;
 		reg = <0>;
+		spi-rx-bus-width = <8>;
+		spi-tx-bus-width = <8>;
 	};
 
 	mt35xu512aba1: flash@1 {
@@ -69,6 +71,8 @@ mt35xu512aba1: flash@1 {
 		m25p,fast-read;
 		spi-max-frequency = <50000000>;
 		reg = <1>;
+		spi-rx-bus-width = <8>;
+		spi-tx-bus-width = <8>;
 	};
 };