vout: opengl: remove duplicate vout_display_opengl_SetViewpoint
vout: opengl: remove duplicate vout_display_opengl_SetViewpoint

xkfz007/vlc,xkfz007/vlc,xkfz007/vlc,xkfz007/vlc,xkfz007/vlc,xkfz007/vlc,xkfz007/vlc