[X86][AVX2] Removed FIXME comment and regenerated test.
[X86][AVX2] Removed FIXME comment and regenerated test.

The comment talked about replacing vpmovzxwd+vpslld+vpsrad with vpmovsxwd - which isn't valid as we're sign extending a <8 x i1> bool vector not an all/nobits <8 x i16>

git-svn-id: 0ff597fd157e6f4fc38580e8d64ab130330d2411@292948 91177308-0d34-0410-b5e6-96231b3b80d8

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