[llvm] [AMDGPU] Add target feature require-naturally-aligned-buffer-access (PR #115479)

[Piotr Sobczak via llvm-commits]

================
@@ -600,6 +601,10 @@ class GCNSubtarget final : public AMDGPUGenSubtargetInfo,
     return UnalignedAccessMode;
   }
 
+  bool requiresNaturallyAlignedBufferAccess() const {
----------------
piotrAMD wrote:

Right, I wasn't sure how to phrase it, and there is already a precedent for "require" (RequiresCOV). HasNaturalAlignmentRequirementBufferAccess?

https://github.com/llvm/llvm-project/pull/115479