* lisp/emacs-lisp/edebug.el: Misc cleanups.

* lisp/emacs-lisp/edebug.el: Misc cleanups.

Move all definitions under the `edebug-` prefix.

(edebug-get-spec): Rename from `get-edebug-spec`.
(edebug-move-cursor): Use `cl-callf`.
(edebug-spec-p): Remove unused function.
(def-edebug-spec, edebug-spec-list, edebug-spec): Remove unused specs
(nothing in there gets instrumented anyway).
(edebug-tracing): Use `declare`.
(edebug-cancel-on-entry): Rename from `cancel-edebug-on-entry`.
(edebug-global-prefix): Rename from `global-edebug-prefix`.
(edebug-global-map): Rename from `global-edebug-map`.

* lisp/emacs-lisp/pcase.el (pcase-PAT): Remove `let`.
(let): Use `declare` instead.
(pcase--edebug-match-macro): Use new name `edebug-get-spec`.