FTP: partly revert eeb7c12807

Since ASCII transfers on FTP means sending CRLF line endings, we should
still keep converting them to LF-only on platforms where text files
typically do not use CRLF.

This also DOES NOT convert existing CRLF line endings on ASCII uploads
but only does stand-alone LF => CRLF.

Regression from eeb7c12807 shipped in 8.10.0

Reported-by: finkjsc on github
Fixes #14873
Closes #14875

tests/runtests.pl

@@ -1497,6 +1497,11 @@ sub singletest_check {
         if($hash{'crlf'}) {
             subnewlines(1, \$_) for @upload;
         }
+        if($hash{'nonewline'}) {
+            # Yes, we must cut off the final newline from the final line
+            # of the upload data
+            chomp($upload[-1]);
+        }
 
         $res = compare($runnerid, $testnum, $testname, "upload", \@out, \@upload);
         if ($res) {