(Merge 3.1) Issue #12012: ssl.PROTOCOL_SSLv2 becomes optional

OpenSSL is now compiled with OPENSSL_NO_SSL2 defined (without the SSLv2
protocol) on Debian: fix the ssl module on Debian Testing and Debian Sid.

Optimize also ssl.get_protocol_name(): speed does matter!
diff --git a/Misc/NEWS b/Misc/NEWS
index 369d0a3..0214c0b 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -80,6 +80,8 @@
 Library
 -------
 
+- Issue #12012: ssl.PROTOCOL_SSLv2 becomes optional.
+
 - Issue #11164: Remove obsolete allnodes test from minidom test.
 
 - Issue #11927: SMTP_SSL now uses port 465 by default as documented.  Patch