Fix -Wreorder warning

src/generic/markuptext.cpp

@@ -123,7 +123,6 @@ public:
           m_dc(dc),
           m_rect(rect),
           m_flags(flags)
-        , m_pos(m_rect.x)
 
         // We don't initialize the base class initial text background colour to
         // the valid value because we want to be able to detect when we revert
@@ -134,6 +133,7 @@ public:
         // but it might affect the caller if it sets the background mode to
         // opaque and draws some text after using us.
         , m_origTextBackground(dc.GetTextBackground())
+        , m_pos(m_rect.x)
     {
     }