MAINTAINERS: ksmbd: add cifs_common directory to ksmbd entry

The codes that shared between cifs and ksmbd will move into the cifs_common
directory. This patch add it to the ksmbd entry in the MAINTAINERS file.
Signed-off-by: NNamjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: NSteve French <stfrench@microsoft.com>

MAINTAINERS

@@ -9946,6 +9946,7 @@ M:	Hyunchul Lee <hyc.lee@gmail.com>
 L:	linux-cifs@vger.kernel.org
 S:	Maintained
 T:	git git://git.samba.org/ksmbd.git
+F:	fs/cifs_common/
 F:	fs/ksmbd/
 
 KERNEL UNIT TESTING FRAMEWORK (KUnit)