can: update MAINTAINERS and Documentation

Changed MAINTAINERS file to add Documentation/networking/can.txt to the list of
maintained files.

can.txt:
- Globally changed Socket CAN to SocketCAN
- Removed section 3.3 from the document
- Updated Section 7
- Corrected a few simple typos
Acked-by: Oliver Hartkopp <socketcan@hartkopp.net>
Signed-off-by: John Whitmore <johnfwhitmore@gmail.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

MAINTAINERS

@@ -2012,6 +2012,7 @@ L:	linux-can@vger.kernel.org
 W:	http://gitorious.org/linux-can
 T:	git git://gitorious.org/linux-can/linux-can-next.git
 S:	Maintained
+F:	Documentation/networking/can.txt
 F:	net/can/
 F:	include/linux/can/core.h
 F:	include/uapi/linux/can.h