Revert "COFF: Do not use VirtualSize section header field for directive sections."

This reverts commit r241386 because the issue is addressed in LLVM (r241387).

llvm-svn: 241388
diff --git a/lld/COFF/InputFiles.cpp b/lld/COFF/InputFiles.cpp
index 9b2b9b3..3bb3c6f 100644
--- a/lld/COFF/InputFiles.cpp
+++ b/lld/COFF/InputFiles.cpp
@@ -136,8 +136,7 @@
     if (Name == ".drectve") {
       ArrayRef<uint8_t> Data;
       COFFObj->getSectionContents(Sec, Data);
-      Directives = std::string((const char *)Data.data(),
-                               Sec->SizeOfRawData);
+      Directives = std::string((const char *)Data.data(), Data.size());
       continue;
     }
     if (Name.startswith(".debug"))