Change QT_FILE_SELECTORS to be comma separated

It is not full paths being used, so switching to comma does not require
different environment variables per platform nor does it appear to be
platform dependent.

Change-Id: I219517d740fa7385e923a9e09cb7e241378f85ba
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>
Reviewed-by: David Faure <david.faure@kdab.com>

src/corelib/io/qfileselector.cpp

@@ -328,11 +328,7 @@ void QFileSelectorPrivate::updateSelectors()
     if (!sharedData->staticSelectors.isEmpty())
         return; //Already loaded
 
-#if defined(Q_OS_WIN)
-    QLatin1Char pathSep(';');
-#else
-    QLatin1Char pathSep(':');
-#endif
+    QLatin1Char pathSep(',');
     QStringList envSelectors = QString::fromLatin1(qgetenv("QT_FILE_SELECTORS"))
                                 .split(pathSep, QString::SkipEmptyParts);
     if (envSelectors.count())