sunxi:disp: Use msleep instead LCD_delay_ms

LCD_delay_ms do same that kernel msleep
This patch remove LCD_delay_ms and use msleep instead.

v2: Use msleep instead msleep_interruptible

Signed-off-by: Alexsey Shestacov <wingrime@linux-sunxi.org>
Acked-by: Jari Helaakoski <tekkuli@gmail.com>