MAINTAINERS: add devicetree bindings to Input Drivers section

To avoid changes to input bindings not reaching linux-input reviewers
add an appropriate file pattern to the MAINTAINERS entry.

Reported-by: Heiko Stübner <[email protected]>
Signed-off-by: Andreas Färber <[email protected]>
Reviewed-by: Heiko Stuebner <[email protected]>
Signed-off-by: Dmitry Torokhov <[email protected]>

Author: afaerber

MAINTAINERS

@@ -5476,6 +5476,7 @@ F:	drivers/input/
 F:	include/linux/input.h
 F:	include/uapi/linux/input.h
 F:	include/linux/input/
+F:	Documentation/devicetree/bindings/input/
 
 INPUT MULTITOUCH (MT) PROTOCOL
 M:	Henrik Rydberg <[email protected]>