careadlinkat: stop exporting careadlinkatcwd Only Emacs used it directly, and Emacs no longer needs it. * NEWS: Document this simplification. * lib/areadlink.c (careadlinkatcwd): Move here from careadlinkat.c, and make it static. Include <stdlib.h>, for abort, and unistd.h, for readlink. * lib/careadlinkat.c (careadlinkatcwd): Move to areadlink.c. Don't include stdlib.h; no longer needed. * lib/careadlinkat.h (careadlinkatcwd): Remove decl. * lib/relocwrapper.c: Adjust comment to match new dependencies. * modules/areadlink (Depends-on): Add readlink. (Maintainer): Add self. * modules/careadlinkat (Depends-on): Remove readlink.