[clangd][nfc] Correct header name in comment

git-svn-id: https://llvm.org/svn/llvm-project/clang-tools-extra/trunk@328149 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/clangd/index/Index.h b/clangd/index/Index.h
index 1b752b6..42f23ce 100644
--- a/clangd/index/Index.h
+++ b/clangd/index/Index.h
@@ -1,4 +1,4 @@
-//===--- Symbol.h -----------------------------------------------*- C++-*-===//
+//===--- Index.h ------------------------------------------------*- C++-*-===//
 //
 //                     The LLVM Compiler Infrastructure
 //