[ENV][D18] Enable usage of new seco_fdt_overlay apply_all cmd

This removes the usage of the previous implementation in the
environment.

include/configs/seco_imx8mp_d18.h

@@ -311,8 +311,7 @@
 	fdt addr ${fdt_loadaddr}; fdt resize ${fdt_resize}; \
 	if test -n "${fdt_overlay_carrier_file}"; then run fdt_overlay_carrier_cmd; fi; \
 	seco_config fdtoverlay ; \
-	seco_eeprom_manager env SECO_EEPROM_I2C_BUS SECO_EEPROM_I2C_ADDR; \
-	run fdt_overlay_apply_all; \
+	seco_fdt_overlay apply_all; \
 	if test -n "${fdt_overlay_per_cmd}"; then run fdt_overlay_per_cmd; fi; \