Convert CONFIG_MISC_INIT_R to Kconfig

This converts the following to Kconfig:
   CONFIG_MISC_INIT_R

Signed-off-by: Adam Ford <aford173@gmail.com>
[trini: Update the defaults logic slightly]
Signed-off-by: Tom Rini <trini@konsulko.com>
diff --git a/configs/colibri_imx6_defconfig b/configs/colibri_imx6_defconfig
index a192361..d86c087 100644
--- a/configs/colibri_imx6_defconfig
+++ b/configs/colibri_imx6_defconfig
@@ -15,6 +15,7 @@
 CONFIG_BOOTDELAY=1
 # CONFIG_CONSOLE_MUX is not set
 CONFIG_SUPPORT_RAW_INITRD=y
+CONFIG_MISC_INIT_R=y
 CONFIG_VERSION_VARIABLE=y
 # CONFIG_DISPLAY_BOARDINFO is not set
 CONFIG_DISPLAY_BOARDINFO_LATE=y