runtime: move matchit.vim to /pack/dist/opt/

Align matchit.vim with upstream Vim. We don't want to maintain a fork of
matchit.vim; our small changes should be sent to
https://github.com/chrisbra/matchit

scripts/vim-patch.sh

@@ -178,12 +178,6 @@ preprocess_patch() {
   # Remove vimrc_example.vim
   local na_vimrcexample='vimrc_example\.vim'
   2>/dev/null $nvim --cmd 'set dir=/tmp' +'g@^diff --git a/runtime/\<\%('${na_vimrcexample}'\)\>@norm! d/\v(^diff)|%$
-' +w +q "$file"
-
-  # Rename src/ paths to src/nvim/
-  LC_ALL=C sed -e 's/\( [ab]\/src\)/\1\/nvim/g' \
-    "$file" > "$file".tmp && mv "$file".tmp "$file"
-
 ' +w +q "$file"
 
   # Rename src/ paths to src/nvim/