ColdFire: Remove rogue 'CONFIG_SYS_NO_FLASH' embedded within another CONFIG_ name

The original commit for the MCF54418TWR ColdFire development board
support defined a 'CONFIG_SYS_FAULT_ECCONFIG_SYS_NO_FLASHHO_LINK_DOWN'
which obviously has a rogue 'CONFIG_SYS_NO_FLASH' embedded in the
intended 'CONFIG_SYS_FAULT_ECHO_LINK_DOWN' define.

Signed-off-by: Lothar Waßmann <LW@KARO-electronics.de>