IB/qib: Clear WAIT_SEND flags when setting QP to error state

If these flags are set when the QP is transitioned to the error state,
it will wait until the flags are cleared, which may never happen if
the error transition is due to a link going down.

Signed-off-by: Mike Marciniszyn <mike.marciniszyn@qlogic.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>