Flip the origin of global map texture

Now it's consistent with the overlay texture.

apps/openmw/mwgui/mapwindow.cpp

@@ -746,7 +746,7 @@ namespace MWGui
 
         mGlobalMapTexture.reset(new osgMyGUI::OSGTexture(mGlobalMapRender->getBaseTexture()));
         mGlobalMapImage->setRenderItemTexture(mGlobalMapTexture.get());
-        mGlobalMapImage->getSubWidgetMain()->_setUVSet(MyGUI::FloatRect(0.f, 0.f, 1.f, 1.f));
+        mGlobalMapImage->getSubWidgetMain()->_setUVSet(MyGUI::FloatRect(0.f, 1.f, 1.f, 0.f));
 
         mGlobalMapOverlayTexture.reset(new osgMyGUI::OSGTexture(mGlobalMapRender->getOverlayTexture()));
         mGlobalMapOverlay->setRenderItemTexture(mGlobalMapOverlayTexture.get());

apps/openmw/mwrender/globalmap.cpp

@@ -165,7 +165,7 @@ namespace MWRender
                         int vertexY = static_cast<int>(float(cellY) / float(mCellSize) * 9);
 
                         int texelX = (x-mMinX) * mCellSize + cellX;
-                        int texelY = (mHeight-1) - ((y-mMinY) * mCellSize + cellY);
+                        int texelY = (y-mMinY) * mCellSize + cellY;
 
                         unsigned char r,g,b;