scripts/functions: properly catch failure in CT_Test* helpers

So we get caught by the trap-handler and
have a chance to run the debug-shell.

Signed-off-by: "Yann E. MORIN" <yann.morin.1998@free.fr>
Cc: Johannes Stezenbach <js@sig21.net>

 # m68k specific configuration file

 ## depends on EXPERIMENTAL

 ##

 ## select ARCH_SUPPORTS_32

 ## select ARCH_DEFAULT_32

 ## select ARCH_DEFAULT_BE

 ## select ARCH_SUPPORTS_WITH_CPU

 ##

 ## help The m68k architecture