Fix XMPP code detection on s_client starttls xmpp

 * Some XMPP Servers (OpenFire) use double quotes.
 * This makes s_client starttls work with this servers.
 * Tested with OpenFire servers from http://xmpp.net/ ::

     openssl s_client -connect coderollers.com:5222 -starttls xmpp

apps/s_client.c

diff --git a/apps/s_client.c b/apps/s_client.c
index 61ad291..c38c42e 100644
--- a/apps/s_client.c
+++ b/apps/s_client.c
@@ -1673,7 +1673,8 @@
 		    "xmlns='jabber:client' to='%s' version='1.0'>", host);
 		seen = BIO_read(sbio,mbuf,BUFSIZZ);
 		mbuf[seen] = 0;
-		while (!strstr(mbuf, "<starttls xmlns='urn:ietf:params:xml:ns:xmpp-tls'"))
+		while (!strstr(mbuf, "<starttls xmlns='urn:ietf:params:xml:ns:xmpp-tls'") &&
+				!strstr(mbuf, "<starttls xmlns=\"urn:ietf:params:xml:ns:xmpp-tls\""))
 			{
 			if (strstr(mbuf, "/stream:features>"))
 				goto shut;