NOTE: Apply to --target=arm-none-symbianelf builds only.

This works around the problem of TRK overshooting line-wise stepping by a few
instructions. This is not a gdb problem, but a TRK problem, but currently
easier to workaround on the gdb side. It's sufficient to apply for the 
arm-none-symbianelf targeted gdbs only as TRK is the only probe known to have
this problem.

--- a/gdb/infrun.c
+++ b/gdb/infrun.c
@@ -4754,9 +4754,9 @@ infrun: not switching back to stepped thread, it has vanished\n");
       return;
     }
 
-  if ((stop_pc == stop_pc_sal.pc)
+  if (1 /* (stop_pc == stop_pc_sal.pc)
       && (ecs->event_thread->current_line != stop_pc_sal.line
- 	  || ecs->event_thread->current_symtab != stop_pc_sal.symtab))
+ 	  || ecs->event_thread->current_symtab != stop_pc_sal.symtab) */)
     {
       /* We are at the start of a different line.  So stop.  Note that
          we don't stop if we step into the middle of a different line.