AVX512: Implemented encoding and intrinsics for VPBROADCASTB/W/D/Q instructions.

Differential Revision: http://reviews.llvm.org/D13884

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@250819 91177308-0d34-0410-b5e6-96231b3b80d8
12 files changed