fbdev: sh_mobile_lcdc: remove runtime PM calls from the notifier

The notifier function calls sh_mobile_lcdc_stop() and
sh_mobile_lcdc_start(), which already take care about the runtime PM
state. Remove redundant calls.

Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>