drivers/rtc/Kconfig: move DS2404 entry where it belongs

Move the DS2404 entry together with the other Dallas entries, and add
Maxim so that it looks nicer (and more correct, too.)

Signed-off-by: Jean Delvare <jdelvare@suse.de>
Cc: Sven Schnelle <svens@stackframe.org>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>