Add another missing header that used to be included transitively.

llvm-svn: 230927

llvm/include/llvm/ProfileData/CoverageMapping.h

@@ -23,6 +23,7 @@
 #include "llvm/Support/ErrorOr.h"
 #include "llvm/Support/raw_ostream.h"
 #include <system_error>
+#include <tuple>
 
 namespace llvm {
 class IndexedInstrProfReader;