qed*: Set rdma generic functions prefix

Rename the functions common to both iWARP and RoCE to have a prefix of
_rdma_ instead of _roce_.

Signed-off-by: Michal Kalderon <Michal.Kalderon@cavium.com>
Signed-off-by: Yuval Mintz <Yuval.Mintz@cavium.com>
Signed-off-by: David S. Miller <davem@davemloft.net>