escape properly the file names in #line for printer/destructor

Reported by Jannick.
http://lists.gnu.org/archive/html/bug-bison/2017-05/msg00001.html

"Amusingly" enough, we have the same problem with %defines when the
parser file name has backslashes or quotes: we generate #includes with
an incorrect C string.

* src/output.c (prepare_symbol_definitions): Escape properly the file
names before passing them to M4.
* data/bison.m4, data/lalr1.cc: Don't simply put the file name between
two quotes (that should have been strong enough a smell...), expect
the string to be properly quoted.
* tests/synclines.at: New tests to check this.

THANKS

@@ -64,6 +64,7 @@ Guido Trentalancia        [email protected]
 H. Merijn Brand           [email protected]
 Hans Åberg                [email protected]
 Jan Nieuwenhuizen         [email protected]
+Jannick                   [email protected]
 Jerry Quinn               [email protected]
 Jesse Thilo               [email protected]
 Jim Kent                  [email protected]