Added a table for intrinsics on X86. 
It should remove dosens of lines in handling instrinsics (in a huge switch) and give an easy way to add new intrinsics.
I did not completed to move al intrnsics to the table, I'll do this in the upcomming commits.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@215826 91177308-0d34-0410-b5e6-96231b3b80d8