MAINTAINERS: add missing extcon directory
MAINTAINERS: add missing extcon directory

Add the missing extcon directory to maintain them.  When using
get_maintainer.pl, the result should include the correct maintainer
information.

Signed-off-by: Chanwoo Choi <42eed19c0f56a8d487deac90c6d19d6364b7ba73@samsung.com>
Signed-off-by: Andrew Morton <5c1e68b099950c134891f0b6e179498a8ebe9cf9@linux-foundation.org>
Signed-off-by: Linus Torvalds <69652caca27c8b940640ad396ab71f93cacec34f@linux-foundation.org>

KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs