Allow the application to always set "read receipt" for one way messages
the library shell discard the flag in case the message is sent via
"send/receive". this change will improve performance and will lower amount of
receipt messages.

Change-Id: I2b6eaba0a19f9f73780bf1aff0d60865d7c0253a
Signed-off-by: Eyal Salomon <esalomon@mellanox.com>