qmljs: put file specific logs in anonymous namespace

putting file specific log categories in anonymous namespace
avoid the possibility of nameclashes.

Change-Id: I17a07015ffe1c539824fcfcbc2296335d9225dd1
Reviewed-by: Kai Koehne <kai.koehne@digia.com>

src/libs/qmljs/qmljsicons.cpp

@@ -43,9 +43,11 @@ enum {
     debug = false
 };
 
-namespace QmlJS {
-
+namespace {
 Q_LOGGING_CATEGORY(iconsLog, "qtc.qmljs.icons")
+}
+
+namespace QmlJS {
 
 Icons *Icons::m_instance = 0;