fbdev: sh_mobile_lcdc: fixup B side hsync adjust settings

The lcdc B side horizon output is shifted
if sh_mobile_lcdc_pan() was called.
This patch fixup this issue.
It is tested on R8A7740 Armadillo800eva HDMI output.
Special thanks to Fukushima-san, and Sano-san

Reported-by: Osamu Fukushima <osamu.fukushima.wr@renesas.com>
Signed-off-by: Hideyuki Sano <hideyuki.sano.dn@renesas.com>
Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>