locking/mutex: Disable optimistic spinning on some architectures

The optimistic spin code assumes regular stores and cmpxchg() play nice;
this is found to not be true for at least: parisc, sparc32, tile32,
metag-lock1, arc-!llsc and hexagon.

There is further wreckage, but this in particular seemed easy to
trigger, so blacklist this.

Opt in for known good archs.

Signed-off-by: Peter Zijlstra <[email protected]>
Reported-by: Mikulas Patocka <[email protected]>
Cc: David Miller <[email protected]>
Cc: Chris Metcalf <[email protected]>
Cc: James Bottomley <[email protected]>
Cc: Vineet Gupta <[email protected]>
Cc: Jason Low <[email protected]>
Cc: Waiman Long <[email protected]>
Cc: "James E.J. Bottomley" <[email protected]>
Cc: Paul McKenney <[email protected]>
Cc: John David Anglin <[email protected]>
Cc: James Hogan <[email protected]>
Cc: Linus Torvalds <[email protected]>
Cc: Davidlohr Bueso <[email protected]>
Cc: [email protected]
Cc: Benjamin Herrenschmidt <[email protected]>
Cc: Catalin Marinas <[email protected]>
Cc: Russell King <[email protected]>
Cc: Will Deacon <[email protected]>
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Ingo Molnar <[email protected]>

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