Fix parameter name comments using clang-tidy. NFC.

This patch applies clang-tidy's bugprone-argument-comment tool
to LLVM, clang and lld source trees. Here is how I created this
patch:

$ git clone https://github.com/llvm/llvm-project.git
$ cd llvm-project
$ mkdir build
$ cd build
$ cmake -GNinja -DCMAKE_BUILD_TYPE=Debug \
    -DLLVM_ENABLE_PROJECTS='clang;lld;clang-tools-extra' \
    -DCMAKE_EXPORT_COMPILE_COMMANDS=On -DLLVM_ENABLE_LLD=On \
    -DCMAKE_C_COMPILER=clang -DCMAKE_CXX_COMPILER=clang++ ../llvm
$ ninja
$ parallel clang-tidy -checks='-*,bugprone-argument-comment' \
    -config='{CheckOptions: [{key: StrictMode, value: 1}]}' -fix \
    ::: ../llvm/lib/**/*.{cpp,h} ../clang/lib/**/*.{cpp,h} ../lld/**/*.{cpp,h}

llvm-svn: 366177
diff --git a/clang/lib/CodeGen/CGBuilder.h b/clang/lib/CodeGen/CGBuilder.h
index 7a26ae2..68c8c64 100644
--- a/clang/lib/CodeGen/CGBuilder.h
+++ b/clang/lib/CodeGen/CGBuilder.h
@@ -263,7 +263,7 @@
         Addr.getElementType(), Addr.getPointer(), Idx0, Idx1, Name));
     llvm::APInt Offset(
         DL.getIndexSizeInBits(Addr.getType()->getPointerAddressSpace()), 0,
-        /*IsSigned=*/true);
+        /*isSigned=*/true);
     if (!GEP->accumulateConstantOffset(DL, Offset))
       llvm_unreachable("offset of GEP with constants is always computable");
     return Address(GEP, Addr.getAlignment().alignmentAtOffset(