admin/cus-test,el misc updates

admin/cus-test,el misc updates

Mainly for some files listed in loaddefs.el now being in subdirs that
are not in load-path.

* admin/cus-test.el (cus-test-libs-noloads): Add dunnet in the defvar.
(dunnet): Don't always load it.
(viper-mode): Only set if interactive.
(cus-test-load-custom-loads): Load dunnet if necessary.
(cus-test-load-1): New macro, with common code from cus-test-load-libs
and cus-test-libs.
(cus-test-load-libs, cus-test-libs): Use cus-test-load-1 macro.
Update for cus-test-get-autoload-deps changed result.
(cus-test-get-autoload-deps): Simplify.  Return file names as they
appear in loaddefs.el (directory parts are needed now that not all
lisp subdirs are in load-path).
(cus-test-deps): Explicitly skip dunnet.