Port libmyth.pro to work with Qt5 + Qt4.

mythtv/libs/libmyth/libmyth.pro

@@ -1,19 +1,29 @@
 include ( ../../settings.pro )
 
+QT += network xml sql script
+contains(QT_VERSION, ^5\\.[0-9]\\..*) {
+QT += widgets
+}
+
 TEMPLATE = lib
 TARGET = myth-$$LIBVERSION
 CONFIG += thread dll
 target.path = $${LIBDIR}
 INSTALLS = target
 DEFINES += MYTH_API
 
+QMAKE_CLEAN += $(TARGET) $(TARGETA) $(TARGETD) $(TARGET0) $(TARGET1) $(TARGET2)
 
-QT += network xml sql script
-contains(QT_VERSION, ^5\\.[0-9]\\..*) {
-QT += widgets
-}
+POSTINC =
 
-QMAKE_CLEAN += $(TARGET) $(TARGETA) $(TARGETD) $(TARGET0) $(TARGET1) $(TARGET2)
+contains(INCLUDEPATH, /usr/include) {
+  POSTINC += /usr/include
+  INCLUDEPATH -= /usr/include
+}
+contains(INCLUDEPATH, /usr/local/include) {
+  POSTINC += /usr/local/include
+  INCLUDEPATH -= /usr/local/include
+}
 
 # Input
 HEADERS += audio/audiooutput.h audio/audiooutputbase.h audio/audiooutputnull.h