imx: Drop unneeded phandle in FIT template

Adding a phandle to a template node is not allowed, since when the node is
instantiated multiple times, we end up with duplicate phandles.

Drop this invalid constructs.

Signed-off-by: Simon Glass <sjg@chromium.org>
Acked-by: Tim Harvey <tharvey@gateworks.com>
diff --git a/arch/arm/dts/imx8mm-u-boot.dtsi b/arch/arm/dts/imx8mm-u-boot.dtsi
index 035282b..6085128 100644
--- a/arch/arm/dts/imx8mm-u-boot.dtsi
+++ b/arch/arm/dts/imx8mm-u-boot.dtsi
@@ -140,7 +140,7 @@
 			configurations {
 				default = "@config-DEFAULT-SEQ";
 
-				binman_configuration: @config-SEQ {
+				@config-SEQ {
 					description = "NAME";
 					fdt = "fdt-SEQ";
 					firmware = "uboot";