IB/mthca: Remove checks for srq->first_free < 0
The SRQ receive posting functions make sure that srq->first_free never
becomes negative, so we can remove tests of whether it is negative.
Signed-off-by: Eli Cohen <eli@mellanox.co.il>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
authored by Eli Cohen and committed by Roland Dreier 1203c42e 1d96354e