Ensure that PC is decremented after a breakpoint on Linux.

2013-03-19  Anton Kolesov   <anton.kolesov@synopsys.com>
    * arc-linux-tdep.c (arc_linux_init_abi): Set decr_pc to 2.
Merge pull request #2 from anthony-kolesov/arc_4_4-gdb-6_8-dev

Ensure that PC is decremented after a breakpoint on Linux.