treewide: Migrate CONFIG_BOARD_EARLY_INIT_R to Kconfig

Migrate the CONFIG_BOARD_EARLY_INIT_R option to Kconfig.

Signed-off-by: Mario Six <mario.six@gdsys.cc>
diff --git a/configs/T1042D4RDB_SECURE_BOOT_defconfig b/configs/T1042D4RDB_SECURE_BOOT_defconfig
index 5e69872..4619567 100644
--- a/configs/T1042D4RDB_SECURE_BOOT_defconfig
+++ b/configs/T1042D4RDB_SECURE_BOOT_defconfig
@@ -13,6 +13,7 @@
 # CONFIG_CONSOLE_MUX is not set
 CONFIG_SYS_CONSOLE_IS_IN_ENV=y
 CONFIG_BOARD_EARLY_INIT_F=y
+CONFIG_BOARD_EARLY_INIT_R=y
 CONFIG_HUSH_PARSER=y
 CONFIG_CMD_IMLS=y
 CONFIG_CMD_GREPENV=y