Don't save internal--text-quoting-flag.

Don't save internal--text-quoting-flag.

It gets set in emacs.c at startup, and should reflect the environment
in which we are running, not the environment in which the lisp code
was loaded and dumped.

This manifested indirectly in the Python documentation, where due to
the use of format-message inside a defmacro body, the quoting style
used in some macro-generated functions was dependent on the use of
UTF-8 in the environment when the file was byte-compiled.

* lisp/loadup.el: Don't save internal--text-quoting-flag.