ARM: shmobile: r8a7791: Don't set plat_sci_port scbrr_algo_id field

The field will be removed from the sh-sci driver. Don't set it and let
the driver handle baud rate calculation internally.

Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>