Fix a typo in datagram.c and sctp/socket.c.

Hi,
This patch fixes a typo in net/core/datagram.c and in net/sctp/socket.c

Regards,
David Shwartz

Signed-off-by: David Shwartz <dshwatrz@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>