Convert CONFIG_SYS_CONSOLE_IS_IN_ENV and CONFIG_CONSOLE_MUX to Kconfig

This converts the following to Kconfig:
   CONFIG_SYS_CONSOLE_IS_IN_ENV
   CONFIG_CONSOLE_MUX

Signed-off-by: Simon Glass <sjg@chromium.org>
[trini: Re-order, re-migrate]
Signed-off-by: Tom Rini <trini@konsulko.com>
diff --git a/configs/s5pc210_universal_defconfig b/configs/s5pc210_universal_defconfig
index 1f14566..e956e7c 100644
--- a/configs/s5pc210_universal_defconfig
+++ b/configs/s5pc210_universal_defconfig
@@ -3,6 +3,7 @@
 CONFIG_ARCH_EXYNOS4=y
 CONFIG_TARGET_S5PC210_UNIVERSAL=y
 CONFIG_DEFAULT_DEVICE_TREE="exynos4210-universal_c210"
+CONFIG_SYS_CONSOLE_IS_IN_ENV=y
 CONFIG_HUSH_PARSER=y
 CONFIG_SYS_PROMPT="Universal # "
 CONFIG_CMD_BOOTZ=y