rds: tcp: various endian-ness fixes

rds: tcp: various endian-ness fixes

Found when testing between sparc and x86 machines on different
subnets, so the address comparison patterns hit the corner cases and
brought out some bugs fixed by this patch.

Orabug: 26289770

(Cherry-pick of upstream commit 00354de5779db4aa9c019db787ef89bd1a6b149b)

Signed-off-by: Sowmini Varadhan <sowmini.varadhan@oracle.com>
Tested-by: Imanti Mendez <imanti.mendez@oracle.com>
Acked-by: Santosh Shilimkar <santosh.shilimkar@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>