rds: Return proper "tos" value to user-space

The proper "tos" value needs to be returned
to user-space (sockopt RDS_INFO_CONNECTIONS).

Fixes: 3eb45036 ("rds: add type of service(tos) infrastructure")
Signed-off-by: Gerd Rausch <gerd.rausch@oracle.com>
Reviewed-by: Zhu Yanjun <yanjun.zhu@oracle.com>
Signed-off-by: Santosh Shilimkar <santosh.shilimkar@oracle.com>