[Outliner] Remove no red zone requirment for AArch64
[Outliner] Remove no red zone requirment for AArch64

AArch64 doesn't require -mno-red-zone; stack fixups are sufficient here. This was
unnecessarily copied over from the X86 target.

(You can now outline with red zones! Yay!)

Removing the requirement passes all Single/MultiSource tests.



git-svn-id: 0ff597fd157e6f4fc38580e8d64ab130330d2411@298734 91177308-0d34-0410-b5e6-96231b3b80d8

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