sticon: remove no-op sticon_set_origin()

We don't need to call vc->vc_sw->con_set_origin() from set_origin()
if it is no-op.

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Link: https://lore.kernel.org/r/20200915000019.3422-2-penguin-kernel@I-love.SAKURA.ne.jp
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>