Fix a funny typo. Thanks to Aaron Ballman for noticing.

llvm-svn: 186532
diff --git a/llvm/lib/Support/Windows/Path.inc b/llvm/lib/Support/Windows/Path.inc
index d51332e..2b04318 100644
--- a/llvm/lib/Support/Windows/Path.inc
+++ b/llvm/lib/Support/Windows/Path.inc
@@ -1054,7 +1054,7 @@
                            OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL, NULL);
   if (H == INVALID_HANDLE_VALUE) {
     error_code EC = windows_error(::GetLastError());
-    // Provide a better error massage when trying to open directories.
+    // Provide a better error message when trying to open directories.
     // This only runs if we failed to open the file, so there is probably
     // no performances issues.
     if (EC != windows_error::access_denied)