docs: remove double carriage-return

The double carriage return would silence a warning due to a missing
.clang-format.  Permit the error to bubble through.

git-svn-id: svn://svn.chromium.org/llvm-project/cfe/trunk/tools/clang-format@221107 0b72dbe1-c17f-4bc7-b9db-2b4152be0356
diff --git a/clang-format.py b/clang-format.py
index 487b9ed..3bb89e0 100644
--- a/clang-format.py
+++ b/clang-format.py
@@ -3,7 +3,7 @@
 # - Add to your .vimrc:
 #
 #   map <C-I> :pyf <path-to-this-file>/clang-format.py<cr>
-#   imap <C-I> <c-o>:pyf <path-to-this-file>/clang-format.py<cr><cr>
+#   imap <C-I> <c-o>:pyf <path-to-this-file>/clang-format.py<cr>
 #
 # The first line enables clang-format for NORMAL and VISUAL mode, the second
 # line adds support for INSERT mode. Change "C-I" to another binding if you