RFR: 8200168: Remove DONT_USE_REGISTER_DEFINES on Sparc

[Per Liden]

Could I please get a second review on this? Vladimir?

/Per

On 03/23/2018 11:29 AM, Per Liden wrote:
> Hi,
> 
> Please review this patch to remove register macros on Sparc, as 
> discussed here: 
> http://mail.openjdk.java.net/pipermail/hotspot-compiler-dev/2018-March/028541.html 
> 
> 
> Bug: https://bugs.openjdk.java.net/browse/JDK-8200168
> Webrev: http://cr.openjdk.java.net/~pliden/8200168/webrev.0
> 
> Testing: Passed hs-tier{1,2}
> 
> /Per