Merge diff always misses the `\ No newline at end of file` mark

For files with conflicts `git diff -- filename` always returns result without the `No newline at end of file` mark.

I was able to reproduce this with all git versions on all platforms.

Steps to reproduce (macOS, 2.32.0 (Apple Git-132)):

``` git init echo "line1\nline2" > eol.txt echo -n "line1\nline2" > noeol.txt git add . git commit -m "initial" git branch br1 echo "line11\nline2" > eol.txt echo -n "line11\nline2" > noeol.txt git add . git commit -m "line1" git checkout br1 echo "line12\nline2" > eol.txt echo -n "line12\nline2" > noeol.txt git add . git commit -m "line2" git merge master git diff -- eol.txt > eol.diff git diff -- noeol.txt > noeol.diff ```

Expected behavior: `noeol.diff` should have `\ No newline at end of file` mark

Actual behavior: Both `eol.diff` and `noeol.diff` have no `\ No newline at end of file` mark

This is my first bug report. Please let me know if I'm missing something.