MAINTAINERS: add maintainer for C-SKY drivers

There are two intc drivers and two clocksource drivers, also include
related dt-bindings' documentations.

Change ren_guo@c-sky.com to guoren@kernel.org

Signed-off-by: Guo Ren <ren_guo@c-sky.com>
Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org>
diff --git a/MAINTAINERS b/MAINTAINERS
index f485597..9a44cef 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -3212,11 +3212,16 @@
 F:	sound/pci/oxygen/
 
 C-SKY ARCHITECTURE
-M:	Guo Ren <ren_guo@c-sky.com>
+M:	Guo Ren <guoren@kernel.org>
 T:	git https://github.com/c-sky/csky-linux.git
 S:	Supported
 F:	arch/csky/
 F:	Documentation/devicetree/bindings/csky/
+F:	drivers/irqchip/irq-csky-*
+F:	Documentation/devicetree/bindings/interrupt-controller/csky,*
+F:	drivers/clocksource/timer-gx6605s.c
+F:	drivers/clocksource/timer-mp-csky.c
+F:	Documentation/devicetree/bindings/timer/csky,*
 K:	csky
 N:	csky