TARGET_REGION_OK_FOR_HW_WATCHPOINT in target vector

[Andrew Cagney]

Hello,

The macro TARGET_REGION_OK_FOR_HW_WATCHPOINT() needs to be moved to the 
target vector.

As part of this, I'd like to propose that its behavour be modified 
slightly.  Instead of returning non-zero to indicate that the vaddr:len 
is ok, it return the number of h/w watchpoint resources that are needed 
to watch vaddr:len.

Thoughts?

Andrew