ARM: dts: sti: fixup sound frame-inversion for stihxxx-b2120.dtsi

frame-inversion is "flag" not "uint32".
This patch fixup it.
Signed-off-by: NKuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Reviewed-by: NPatrice Chotard <patrice.chotard@st.com>
Signed-off-by: NPatrice Chotard <patrice.chotard@st.com>

arch/arm/boot/dts/stihxxx-b2120.dtsi

@@ -46,7 +46,7 @@
 			/* DAC */
 			format = "i2s";
 			mclk-fs = <256>;
-			frame-inversion = <1>;
+			frame-inversion;
 			cpu {
 				sound-dai = <&sti_uni_player2>;
 			};