Convert CONFIG_REMAKE_ELF to Kconfig

This converts the following to Kconfig:
   CONFIG_REMAKE_ELF

Signed-off-by: Alper Nebi Yasak <alpernebiyasak@gmail.com>
diff --git a/configs/imx8mn_beacon_2g_defconfig b/configs/imx8mn_beacon_2g_defconfig
index 1766a43..48503f3 100644
--- a/configs/imx8mn_beacon_2g_defconfig
+++ b/configs/imx8mn_beacon_2g_defconfig
@@ -22,6 +22,7 @@
 CONFIG_SPL=y
 CONFIG_SPL_IMX_ROMAPI_LOADADDR=0x48000000
 CONFIG_LTO=y
+CONFIG_REMAKE_ELF=y
 CONFIG_SYS_LOAD_ADDR=0x40480000
 CONFIG_FIT=y
 CONFIG_FIT_EXTERNAL_OFFSET=0x3000