The 'exception' command allows to test exception handling.
This implementation supports ARM, x86, RISC-V and the following exceptions:
* 'breakpoint' - prefetch abort exception (ARM 32bit only)
* 'unaligned' - data abort exception (ARM only)
* 'undefined' - undefined instruction exception
Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
