bug#30162: 27.0.50; Wrong order of directories in *Deletions*

[Juri Linkov]

This is a regression.  The order of directories in *Deletions* was right
in older versions, but not now.

Steps to reproduce:

0. emacs -Q
1. ‘M-!’ mkdir x y z RET
2. ‘C-x d’ RET
3. ‘D D D’ (select dirs x, y, z for deletion)
4. ‘x’ (dired-do-flagged-delete)

Directories in *Deletions* are reversed:

  z
  y
  x

It seems this is a result of the commit 9ecbdee, but I can't find
a related discussion.

I think we should either reverse the list of buffers at the lowest level
in ‘dired-map-over-marks’ (this might cause backward-compatibility
issues), or don't call ‘nreverse’ twice and remove ‘nreverse’ from
‘dired-internal-do-deletions’.