c-end-of-macro: Handle block coment lines with unescaped NLs correctly

* lisp/progmodes/cc-langs.el (c-last-open-c-comment-start-on-line-re): Make
obsolete, and supersede by ...
(c-open-c-comment-on-logical-line-re): New language variable.

* lisp/progmodes/cc-engine.el (c-end-of-macro): Inside macros, handle
multiline block comments whose line ends are not escaped correctly.
1 job for emacs-27 in 56 minutes and 13 seconds (queued for 2 seconds)
Status Job ID Name Coverage
  Test
passed #4986
test-all

00:56:13