devicetree: Add vendor prefix for FriendlyARM

Guangzhou FriendlyARM Computer Tech Co., Ltd is a Chinese ARM board vendor.

Signed-off-by: James Pettigrew <james@innovum.com.au>
Reviewed-by: Rask Ingemann Lambertsen <ccc94453@vip.cybercity.dk>
Acked-by: Chen-Yu Tsai <wens@csie.org>
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>