configs: Re-sync HUSH options

Move all cases of CONFIG_SYS_HUSH_PARSER out of the config.h files.  Remove
all cases of CONFIG_SYS_PROMPT_HUSH_PS2 as everyone uses the default.

Signed-off-by: Tom Rini <trini@konsulko.com>
diff --git a/configs/mgcoge_defconfig b/configs/mgcoge_defconfig
index 86200fa..9d6adea 100644
--- a/configs/mgcoge_defconfig
+++ b/configs/mgcoge_defconfig
@@ -4,4 +4,5 @@
 CONFIG_FIT=y
 CONFIG_OF_BOARD_SETUP=y
 CONFIG_SYS_EXTRA_OPTIONS="MGCOGE"
+CONFIG_HUSH_PARSER=y
 CONFIG_OF_LIBFDT=y