Fixed bug 1977 - D3D_UpdateClipRect() sets the wrong width for the clip rect

Bithika Mookherjee

SDL_RenderSetClipRect() calls into renderer->UpdateClipRect(renderer).

I am not sure if UpdateClipRect() can point to a number of clip rect update functions, but on my platform it calls D3D_UpdateClipRect().

In that function, the rect to pass to IDirect3DDevice9_SetScissorRect() has it's right field set as:

    r.right = rect->w + rect->w;

But actually, this should be:

    r.right = rect->x + rect->w;