board: rk3288: add more DT files to MAINTAINERS

A number of rk3229/rk3288 DT files are synced from Linux.
Add a maintainer to look after them and to help with
review and testing.

Signed-off-by: Johan Jonker <jbx6244@gmail.com>
Reviewed-by: Kever Yang <kever.yang@rock-chips.com>
diff --git a/board/mqmaker/miqi_rk3288/MAINTAINERS b/board/mqmaker/miqi_rk3288/MAINTAINERS
index 053a5e6..1cb5f79 100644
--- a/board/mqmaker/miqi_rk3288/MAINTAINERS
+++ b/board/mqmaker/miqi_rk3288/MAINTAINERS
@@ -1,6 +1,8 @@
 MIQI
 M:	Jernej Skrabec <jernej.skrabec@siol.net>
 S:	Maintained
+F:	arch/arm/dts/rk3288-miqi.dts
+F:	arch/arm/dts/rk3288-miqi-u-boot.dtsi
 F:	board/mqmaker/miqi_rk3288
 F:	include/configs/miqi_rk3288.h
 F:	configs/miqi-rk3288_defconfig