TMS570 OpenOCD configuration which allows to debug Flash code from start.

The TMS570 seems to not allow stopping of the target directly
after reset by solely "reset halt". Some code is executed anyway.
But when hardware breakpoint in placed on address 0 then
subsequent software reset really stop at PC = 0.
This allows to debug startup code of the Flash.

Signed-off-by: Pavel Pisa <pisa@cmp.felk.cvut.cz>