RFR: Remove obsolete and unused reduce-storeval-barrier optimization code

[Aleksey Shipilev]

On 09/18/2017 03:52 PM, Roman Kennke wrote:
> I re-instated the storeval-barrier in the T_OBJECT versions of the unsafe_load_store intrinsics,
> the same way it has been before I introduced the optimization back then:
> 
> http://cr.openjdk.java.net/~rkennke/remove-reduce-storeval/webrev.03/

Okay, good.

-Aleksey