MAINTAINERS: add the sample directory to the configfs entry

Code samples for configfs don't have an explicit maintainer. Add the
samples directory to the existing configfs entry in MAINTAINERS.

Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>

MAINTAINERS

@@ -4407,6 +4407,7 @@ S:	Supported
 T:	git git://git.infradead.org/users/hch/configfs.git
 F:	fs/configfs/
 F:	include/linux/configfs.h
+F:	samples/configfs/
 
 CONNECTOR
 M:	Evgeniy Polyakov <zbr@ioremap.net>