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/mx28evk_spi_defconfig b/configs/mx28evk_spi_defconfig
index ad939ca..d91822c 100644
--- a/configs/mx28evk_spi_defconfig
+++ b/configs/mx28evk_spi_defconfig
@@ -2,6 +2,7 @@
 CONFIG_TARGET_MX28EVK=y
 CONFIG_SPL=y
 CONFIG_SYS_EXTRA_OPTIONS="ENV_IS_IN_SPI_FLASH"
+CONFIG_HUSH_PARSER=y
 # CONFIG_CMD_IMLS is not set
 # CONFIG_CMD_FLASH is not set
 CONFIG_CMD_GPIO=y