pidgin: fix --without-gui

The options apparently need to be above the dependencies otherwise the
dependencies kick in first. Should deal with [this
comment](https://github.com/Homebrew/homebrew/commit/7537f3663d0ca35e584
8d0a9644ebc86c92d267f#commitcomment-9000071).

Closes #35043.

Signed-off-by: Jack Nagel <jacknagel@gmail.com>