SSH: Fix race condition.

Change-Id: I4f52a2b604db14d088f2416989a502f91a16deab
Reviewed-on: http://codereview.qt.nokia.com/1237Reviewed-by: Qt Sanity Bot <qt_sanity_bot@ovi.com>
Reviewed-by: Daniel Teske <daniel.teske@nokia.com>

src/libs/utils/ssh/sshconnection.cpp

@@ -48,6 +48,7 @@
 
 #include <QtCore/QFile>
 #include <QtCore/QMutex>
+#include <QtCore/QMutexLocker>
 #include <QtNetwork/QNetworkProxy>
 #include <QtNetwork/QTcpSocket>
 
@@ -70,15 +71,12 @@ namespace {
 
     void doStaticInitializationsIfNecessary()
     {
+        QMutexLocker locker(&staticInitMutex);
         if (!staticInitializationsDone) {
-            staticInitMutex.lock();
-            if (!staticInitializationsDone) {
-                Botan::LibraryInitializer::initialize("thread_safe=true");
-                qRegisterMetaType<Utils::SshError>("Utils::SshError");
-                qRegisterMetaType<Utils::SftpJobId>("Utils::SftpJobId");
-                staticInitializationsDone = true;
-            }
-            staticInitMutex.unlock();
+            Botan::LibraryInitializer::initialize("thread_safe=true");
+            qRegisterMetaType<Utils::SshError>("Utils::SshError");
+            qRegisterMetaType<Utils::SftpJobId>("Utils::SftpJobId");
+            staticInitializationsDone = true;
         }
     }
 } // anonymous namespace