Refactor: Simplify boolean expression in modularize

Simplify boolean expressions using `true` and `false` with `clang-tidy`

Patch by Richard Thomson.

Differential Revision: http://reviews.llvm.org/D8534

llvm-svn: 233000
diff --git a/clang-tools-extra/modularize/CoverageChecker.cpp b/clang-tools-extra/modularize/CoverageChecker.cpp
index 17ea107..257dbca 100644
--- a/clang-tools-extra/modularize/CoverageChecker.cpp
+++ b/clang-tools-extra/modularize/CoverageChecker.cpp
@@ -288,7 +288,7 @@
   int HadErrors = Tool.run(new CoverageCheckerFrontendActionFactory(*this));
 
   // If we had errors, exit early.
-  return HadErrors ? false : true;
+  return !HadErrors;
 }
 
 // Called from CoverageCheckerCallbacks to track a header included