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/MIP405_defconfig b/configs/MIP405_defconfig
index 3a012e7..2250011 100644
--- a/configs/MIP405_defconfig
+++ b/configs/MIP405_defconfig
@@ -1,5 +1,6 @@
 CONFIG_PPC=y
 CONFIG_4xx=y
 CONFIG_TARGET_MIP405=y
+CONFIG_HUSH_PARSER=y
 # CONFIG_CMD_SETEXPR is not set
 CONFIG_SYS_NS16550=y