in_aton() gives weird results if it sees a newline at the end of the
input. This patch makes it able to handle such input correctly.

Signed-off-by: Mitch Williams <mitch.a.williams@intel.com>
Acked-by: Jay Vosburgh <fubar@us.ibm.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>