ToolChains: Read SDK settings from Nokia/qtcreator/toolchains.xml

and not from Nokia/toolchains.xml. This makes sure the SDK settings
and the personal settings pathes differ in prefix only.

Change-Id: Ib3a742d28258e86912cb820ff6c9d0c1b44c1763
Reviewed-by: Eike Ziller <eike.ziller@digia.com>

src/plugins/projectexplorer/toolchainmanager.cpp

@@ -142,7 +142,7 @@ void ToolChainManager::restoreToolChains()
     // read all tool chains from SDK
     QFileInfo systemSettingsFile(Core::ICore::settings(QSettings::SystemScope)->fileName());
     QList<ToolChain *> readTcs =
-            restoreToolChains(Utils::FileName::fromString(systemSettingsFile.absolutePath() + QLatin1String(LEGACY_TOOLCHAIN_FILENAME)));
+            restoreToolChains(Utils::FileName::fromString(systemSettingsFile.absolutePath() + QLatin1String(TOOLCHAIN_FILENAME)));
     // make sure we mark these as autodetected!
     foreach (ToolChain *tc, readTcs)
         tc->setAutoDetected(true);