[Alignment][NFC] Remove AllocaInst::setAlignment(unsigned)

Summary:
This is patch is part of a series to introduce an Alignment type.
See this thread for context: http://lists.llvm.org/pipermail/llvm-dev/2019-July/133851.html
See this patch for the introduction of the type: https://reviews.llvm.org/D64790

Reviewers: courbet

Subscribers: jholewinski, arsenm, jvesely, nhaehnle, eraman, hiraditya, cfe-commits, llvm-commits

Tags: #clang, #llvm

Differential Revision: https://reviews.llvm.org/D68141

llvm-svn: 373207
diff --git a/llvm/lib/Target/AMDGPU/AMDGPULibCalls.cpp b/llvm/lib/Target/AMDGPU/AMDGPULibCalls.cpp
index ce0a9db..03f056f 100644
--- a/llvm/lib/Target/AMDGPU/AMDGPULibCalls.cpp
+++ b/llvm/lib/Target/AMDGPU/AMDGPULibCalls.cpp
@@ -1430,8 +1430,8 @@
   B.SetInsertPoint(&*ItNew);
   AllocaInst *Alloc = B.CreateAlloca(RetType, 0,
     std::string(prefix) + UI->getName());
-  Alloc->setAlignment(UCallee->getParent()->getDataLayout()
-                       .getTypeAllocSize(RetType));
+  Alloc->setAlignment(MaybeAlign(
+      UCallee->getParent()->getDataLayout().getTypeAllocSize(RetType)));
   return Alloc;
 }