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/T1040D4RDB_NAND_defconfig b/configs/T1040D4RDB_NAND_defconfig
index 07a5369..46ff4a7 100644
--- a/configs/T1040D4RDB_NAND_defconfig
+++ b/configs/T1040D4RDB_NAND_defconfig
@@ -17,6 +17,7 @@
 CONFIG_SILENT_CONSOLE=y
 CONFIG_SYS_CONSOLE_IS_IN_ENV=y
 CONFIG_BOARD_EARLY_INIT_F=y
+CONFIG_BOARD_EARLY_INIT_R=y
 # CONFIG_SPL_FRAMEWORK is not set
 CONFIG_SPL_ENV_SUPPORT=y
 CONFIG_SPL_I2C_SUPPORT=y