Several problems are present.

The first is that _write returns 0 instead of the
number of samples. We solve it by returning
nsamps.

The second is that _read may return less samples at
the beginning and we don't want to exit for that.
We solve it also by returning nsamps.
(We still need to log more in this, to be done in the
next commit.)

The third is that after initialization we don't send
anything for a while, time for the softmodem to finish
its init. This generates lots of "RX overrun".
We solve it by disabling TX and RX modules after init
and then in trx_brf_start we activate them again (and
also call bladerf_sync_config, which seems to be
mandatory, and bladerf_calibrate_dc, which may be avoided,
perhaps).

Maybe not the end of the story. Sometimes it works, UE connects,
traffic is fine (tested only with 5MHz). Sometimes it does not,
UE does not connect, or it connects but then traffic is bad,
especially uplink.

To be refined.

develop_integration_w24 into develop

Summary or changes:
- work on transmission mode 3 and 4

See merge request !204

only with XFORMS enabled.

The way it was done was confusing.
However, now rank adaptation (if enabled) is not visualized correctly.

fixing handling of ndi/first_tx in dci. commenting out corner case of missed ACK, this needs to be done better

develop_integration_w22 into develop

Summary of changes:
- UE:
  * TDD multiplexing
  * TDD autotest
  * bug fixes: power control management for Msg3, logging
- eNB:
  * CCE allocation fixes
  * S1U port in some configuration files set to 2152 (was 2153)
- support for RedHat enterprise linux 7 and derivatives (CentOS, ...)
  (work provided by RedHat)

See merge request !198