fbdev/core: simplify cursor_state setting in fbcon_ops::cursor()

fbdev/core: simplify cursor_state setting in fbcon_ops::cursor()

There is a switch decicing if cursor should be drawn or not. The whole
switch can be simplified to one line. Do this cleanup as a preparatory
work for the next patch. There, all the CM_* constants are removed.

Signed-off-by: "Jiri Slaby (SUSE)" <jirislaby@kernel.org>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: Helge Deller <deller@gmx.de>
Cc: linux-fbdev@vger.kernel.org
Cc: dri-devel@lists.freedesktop.org
Tested-by: Helge Deller <deller@gmx.de> # parisc STI console
Link: https://lore.kernel.org/r/20240122110401.7289-29-jirislaby@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>