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/pepper_defconfig b/configs/pepper_defconfig
index 7073739..88a672f 100644
--- a/configs/pepper_defconfig
+++ b/configs/pepper_defconfig
@@ -1,6 +1,7 @@
 CONFIG_ARM=y
 CONFIG_TARGET_PEPPER=y
 CONFIG_SPL=y
+CONFIG_HUSH_PARSER=y
 CONFIG_SYS_PROMPT="pepper# "
 # CONFIG_CMD_IMLS is not set
 # CONFIG_CMD_FLASH is not set