bsdinstall/partedit: Replace libdialog with libbsddialog

[asiciliano]

Summary

bsdinstall/partedit and sade(8): Replace (LGPL) libdialog with (BSD-2-Clause) libbsddialog. change only User Iterface everything else is left unchanged (for example an unused variable scripted.c:73:6: warning: variable 'error' set but not used [-Wunused-but-set-variable] int error;). Rewrite diskeditor.c because it uses an API totally incompatible with bsddialog.

Test Plan

The forms are the new components, all others are already in use. Probably sade uses all the dialogs so it is a good test case to continue the replacement process.

[bapt]

simple remark, not mandatory to follow ;), otherwise LGTM

usr.sbin/bsdinstall/partedit/diskmenu.c

60

using asprintf would simplify this

[asiciliano]

Use asprintf()

[asiciliano]

Apply tip

usr.sbin/bsdinstall/partedit/diskmenu.c

60

updated

[mav]

I am not familiar with dialogs or this code. I've tried to look for GEOM-related changes, but haven't found any.