RFR: JDK-8222926: Unify cpu related part of shenandoahBarrierSetC1 and fix build when compiler1 is disabled

[Aleksey Shipilev]

On 5/8/19 3:05 PM, Ao Qi wrote:
>> I changed the synopsis for the bug to: "Shenandoah build fails with --with-jvm-features=-compiler1"
>> -- please change it for the changeset you are pushing.
> 
> Updated: http://cr.openjdk.java.net/~aoqi/8222926/webrev.05/
> 
> I am not a Committers. I need a sponsor:(

I will sponsor.

-Aleksey