Revert "RDS: Make message size limit compliant with spec"

Revert "RDS: Make message size limit compliant with spec"

This change *partially* reverts commit
	3a0891b9a49e42d05519a2f8b33c86267eb63d35

This partial revert is needed due to regression with some RDS
applications. It reverts RDS message size limit changes but retains the
QOS related changes in the data send path.

Orabug: 25472193

Tested-by: Efrain Galaviz <efrain.galaviz@oracle.com>
Signed-off-by: Avinash Repaka <avinash.repaka@oracle.com>
Reviewed-by: Ajaykumar Hotchandani <ajaykumar.hotchandani@oracle.com>