powerpc: Don't silently handle machine checks from userspace

[Micha Nelissen]

From: Scott Wood [mailto:scottwood at freescale.com]
>> Hmm I guess there is no simple solution then, since the "recover"
>> function also prints the kernel messages about the machine check
>> being in kernel mode without having checked whether it really was in
>> kernel mode. In the past the user mode check was in between.
> 
> It shouldn't be that difficult to make it say "in user mode" or "in
> kernel mode" depending on which it was... or just remove that phrase
> altogether and let the following output indicate whether it was in
> kernel mode.

Well printing the correct message is only part of it: do "we" want to pass guarded load errors (RapidIO bus errors) to user space or not? And if we pass them, should we print a kernel message at all?

Micha