[Alignment][Clang][NFC] Add CharUnits::getAsAlign

Summary:
This is a prerequisite to removing `llvm::GlobalObject::setAlignment(unsigned)`.
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, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D68274

llvm-svn: 373592
diff --git a/clang/lib/CodeGen/CGCall.cpp b/clang/lib/CodeGen/CGCall.cpp
index 449b8c4..e851d7b 100644
--- a/clang/lib/CodeGen/CGCall.cpp
+++ b/clang/lib/CodeGen/CGCall.cpp
@@ -3841,7 +3841,7 @@
       AI = CreateTempAlloca(ArgStruct, "argmem");
     }
     auto Align = CallInfo.getArgStructAlignment();
-    AI->setAlignment(llvm::MaybeAlign(Align.getQuantity()));
+    AI->setAlignment(Align.getAsAlign());
     AI->setUsedWithInAlloca(true);
     assert(AI->isUsedWithInAlloca() && !AI->isStaticAlloca());
     ArgMemory = Address(AI, Align);