v3d: Add an isr to the simulator to catch GMP violations.

v3d: Add an isr to the simulator to catch GMP violations.

Otherwise, the simulator raises the GMP interrupt and waits for it to be
handled, and v3d ends up spinning in v3d_hw_tick().  Aborting right when
violation happens gives us a chance to look at the backtrace of whatever
thread triggered the violation.