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/iocon_defconfig b/configs/iocon_defconfig
index 069db16..aa51065 100644
--- a/configs/iocon_defconfig
+++ b/configs/iocon_defconfig
@@ -3,6 +3,7 @@
 CONFIG_TARGET_IOCON=y
 CONFIG_FIT=y
 CONFIG_OF_BOARD_SETUP=y
+CONFIG_HUSH_PARSER=y
 CONFIG_AUTOBOOT_KEYED=y
 CONFIG_AUTOBOOT_STOP_STR=" "
 # CONFIG_CMD_ELF is not set