dirmngr: Require gnutls 3.2
* dirmngr/http.c: Remove gnutls version specific code. (send_request): Factor some code out to ... (run_proxy_connect): new. (mk_proxy_request): new. (mk_std_request): new. * configure.ac (NEED_GNUTLS_VERSION): Require 3.2.
This patch is to factor out some code and also to remove support for
legacy gnutls versions. Note that gnutls 3.2 was released 10 years