Add new vector types for 512-, 1024- and 2048-bit vectors
Those types are needed to implement instructions for Hexagon Vector
Extensions (HVX): 16x32, 16x64, 32x16, 32x32, 32x64, 64x8, 64x16,
64x32, 128x8, 128x16, 256x8, 512x1, and 1024x1.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@253978 91177308-0d34-0410-b5e6-96231b3b80d8