MAINTAINERS: usb gadget: add Mattijs

It seems that Lukasz and Marek could get some help in maintaining the
usb gadget drivers.

Assign myself as maintainer.

Signed-off-by: Mattijs Korpershoek <mkorpershoek@baylibre.com>
Acked-by: Marek Vasut <marex@denx.de>
Acked-by: Lukasz Majewski <lukma@denx.de>
diff --git a/MAINTAINERS b/MAINTAINERS
index 091e6bb..4c7bbbf 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -950,6 +950,7 @@
 
 DFU
 M:	Lukasz Majewski <lukma@denx.de>
+M:	Mattijs Korpershoek <mkorpershoek@baylibre.com>
 S:	Maintained
 T:	git https://source.denx.de/u-boot/custodians/u-boot-dfu.git
 F:	cmd/dfu.c