[vectorIntrinsics] Reduction cleanup for x86

[Rukmannagari, Shravya]

Hi All,
Please find the patch below which cleans up Reduction operations for x86 platforms.
http://cr.openjdk.java.net/~srukmannagar/VectorAPI_ReductionCleanUp/webrev_ReductionCleanUp.00/

Thanks,
Shravya.