gnu: emacs-evil-owl: Update to 0.0.1-2.e8fe5b2.

* gnu/packages/emacs-xyz.scm (emacs-evil-owl): Update to 0.0.1-2.e8fe5b2.
[inputs]: Remove emacs-posframe, which is now an optional dependency.

Signed-off-by: Ludovic Courtès <ludo@gnu.org>