* lisp/emacs-lisp/pcase.el (pcase--match): New smart-constructor function.
(pcase--expand pcase--q1, pcase--app-subst-match): Use it.
(pcase--macroexpand): Handle self-quoting patterns here, expand them to
quote patterns.
(pcase--split-match): Don't hoist or/and here any more.
(pcase--split-equal): Optimize quote patterns as well as ` patterns.
(pcase--flip): New helper macro.
(pcase--u1): Optimize the memq case directly.
Don't handle neither self-quoting nor and/or patterns any more.