[RFA] Make ppc-linux-nat insert/remove breakpoint and watchpoint functions return -1.

[Joel Brobecker]

> Looking at target.h:
> 
> | /* Insert a breakpoint at address BP_TGT->placed_address in the target
> |    machine.  Result is 0 for success, or an errno value.  */
> | 
> | extern int target_insert_breakpoint (struct gdbarch *gdbarch,
> |                                      struct bp_target_info *bp_tgt);
> 

Sorry, scrap that part - I was looking at the wrong method
(I should have been looking at the `hw' one....).

> That being said, it's ultra important IMO in that case that we add the
> documentation wherever missing, because these are used by all ports.

Makes that comment all the more relevant :).

So I guess we'll have to infer the expected behavior from the core
code that calls it. I am hoping that it's the same as with the non
hw versions! :)

-- 
Joel