File qt-4.7.0-always-libpng.patch of Package mingw32-libqt4

--- src/gui/image/qpnghandler.pri	2010-09-10 11:05:25.000000000 +0200
+++ src/gui/image/qpnghandler.pri	2010-10-30 17:03:43.000000000 +0200
@@ -2,7 +2,7 @@
 HEADERS += $$PWD/qpnghandler_p.h
 SOURCES += $$PWD/qpnghandler.cpp
 contains(QT_CONFIG, system-png) {
-    if(unix|win32-g++*): LIBS_PRIVATE  += -lpng
+    if(unix|win32*-g++*): LIBS_PRIVATE  += -lpng
     else:win32:          LIBS += libpng.lib
 
 } else {