[AVX512] Remove leftover code for when i1 was a legal type from the fast isel load/store code.
[AVX512] Remove leftover code for when i1 was a legal type from the fast isel load/store code.

Summary:
I don't think we need this code anymore. It only existed because i1 used to be legal.

There's probably more unneeded code in fast isel still.

Reviewers: guyblank, zvi

Reviewed By: guyblank

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D36652

git-svn-id: 0ff597fd157e6f4fc38580e8d64ab130330d2411@310843 91177308-0d34-0410-b5e6-96231b3b80d8

GPUOpen-Drivers/llvm,GPUOpen-Drivers/llvm,llvm-mirror/llvm,apple/swift-llvm,llvm-mirror/llvm,llvm-mirror/llvm,GPUOpen-Drivers/llvm,apple/swift-llvm,llvm-mirror/llvm,GPUOpen-Drivers/llvm,apple/swift-llvm,GPUOpen-Drivers/llvm,GPUOpen-Drivers/llvm,llvm-mirror/llvm,apple/swift-llvm,llvm-mirror/llvm,apple/swift-llvm,apple/swift-llvm,apple/swift-llvm,GPUOpen-Drivers/llvm,llvm-mirror/llvm,llvm-mirror/llvm,apple/swift-llvm,GPUOpen-Drivers/llvm,llvm-mirror/llvm