[3.5] bpo-30947: Update libexpat from 2.2.1 to 2.2.3 (#3106) by vstinner · Pull Request #3144

[3.5] bpo-30947: Update libexpat from 2.2.1 to 2.2.3 (#3106) by vstinner · Pull Request #3144 · python/cpython

* bpo-30947: Update libexpat from 2.2.1 to 2.2.3

* Add NEWS entry

* Add new loadlibrary.c

* expat_external.h: restore include "pyexpatns.h"

* PCbuild: add expat/loadlibrary.c

* Define XML_POOR_ENTROPY to compile expat

(cherry picked from commit 93d0cb5)