target_enable_exception_callback dead?

[Jim Blandy]

I've noticed that the 'to_enable_exception_callback' and
'to_get_current_exception_event' target vector
entries have only one definition each.  These are in inf-child.c,
which has only dummy definitions for them.

If we were to remove these altogether, there's a reasonable chunk of
code in breakpoint.c and stack.c that would go with it.

Does anyone know of any reason to keep these functions?  The comments
for target_enable_exception_callback in target.h refer to HP-UX and
aCC, but the HP-UX target code in GDB isn't implementing those target
vector entries.