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/snow_defconfig b/configs/snow_defconfig
index 5dbd18a..0b740e9 100644
--- a/configs/snow_defconfig
+++ b/configs/snow_defconfig
@@ -6,6 +6,7 @@
 CONFIG_SPL=y
 CONFIG_FIT=y
 CONFIG_FIT_BEST_MATCH=y
+CONFIG_HUSH_PARSER=y
 CONFIG_SYS_PROMPT="snow # "
 # CONFIG_CMD_IMLS is not set
 CONFIG_CMD_GPIO=y