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/socfpga_n5x_atf_defconfig b/configs/socfpga_n5x_atf_defconfig
index fe41fb0..31346fc 100644
--- a/configs/socfpga_n5x_atf_defconfig
+++ b/configs/socfpga_n5x_atf_defconfig
@@ -13,6 +13,7 @@
 CONFIG_TARGET_SOCFPGA_N5X_SOCDK=y
 CONFIG_IDENT_STRING="socfpga_n5x"
 CONFIG_SPL_FS_FAT=y
+CONFIG_REMAKE_ELF=y
 CONFIG_FIT=y
 CONFIG_SPL_FIT_SIGNATURE=y
 CONFIG_SPL_LOAD_FIT=y