Use LLVM_ATTRIBUTE_UNUSED instead of void casts; NFC

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@274139 91177308-0d34-0410-b5e6-96231b3b80d8

Author: vedantk

tools/llvm-cov/SourceCoverageViewText.cpp

@@ -59,9 +59,11 @@ unsigned getDividerWidth(const CoverageViewOptions &Opts) {
 
 } // anonymous namespace
 
-void SourceCoverageViewText::renderViewHeader(raw_ostream &OS) { (void)OS; }
+void SourceCoverageViewText::renderViewHeader(
+    raw_ostream &OS LLVM_ATTRIBUTE_UNUSED) {}
 
-void SourceCoverageViewText::renderViewFooter(raw_ostream &OS) { (void)OS; }
+void SourceCoverageViewText::renderViewFooter(
+    raw_ostream &OS LLVM_ATTRIBUTE_UNUSED) {}
 
 void SourceCoverageViewText::renderSourceName(raw_ostream &OS) {
   getOptions().colored_ostream(OS, raw_ostream::CYAN) << getSourceName()
@@ -74,11 +76,9 @@ void SourceCoverageViewText::renderLinePrefix(raw_ostream &OS,
     OS << "  |";
 }
 
-void SourceCoverageViewText::renderLineSuffix(raw_ostream &OS,
-                                              unsigned ViewDepth) {
-  (void)OS;
-  (void)ViewDepth;
-}
+void SourceCoverageViewText::renderLineSuffix(
+    raw_ostream &OS LLVM_ATTRIBUTE_UNUSED,
+    unsigned ViewDepth LLVM_ATTRIBUTE_UNUSED) {}
 
 void SourceCoverageViewText::renderViewDivider(raw_ostream &OS,
                                                unsigned ViewDepth) {