PHY: add parameter end_of_burst_delay for TDD

end_of_burst_delay is used to stop TX only "after a while".
If we stop right after effective signal, with USRP B210 and
B200mini, we observe a high EVM on the S subframe (on the
PSS).
A value of 400 (for 30.72MHz) solves this issue. This is
the default.

This default value can be changed in the configuration file.
For example:

RUs = (
    {
       local_rf       = "yes"
         nb_tx          = 1
         nb_rx          = 1
         att_tx         = 20
         att_rx         = 0;
         bands          = [7];
         max_pdschReferenceSignalPower = -27;
         max_rxgain                    = 105;
         eNB_instances  = [0];
         sf_extension = 312;
         end_of_burst_delay = 200;
    }
);

Here we would set a value of 200.

The value to put in the configuration file is for
30.72MHz. The value is scaled accordingly at runtime
(thus only one value to set for every RB configuration,
25, 50 or 100, leading to less problems when adapting
configuration files).

This option is for experts and should not be changed
randomly.
14 jobs for tdd-fixes-2019-w11 in 0 seconds (queued for 16 minutes and 5 seconds)
Status Job ID Name Coverage
  External
passed Analysis with cppcheck

00:05:55

passed Build UE-ethernet

00:02:09

passed Build basic-sim

00:00:03

passed Build eNb-USRP

00:00:07

passed Build eNb-ethernet

00:00:07

passed Build phy-sim

00:04:24

passed Test L2-sim

00:06:17

passed Test basic-sim

00:11:41

passed Test phy-sim

00:10:37

passed Test-IF4p5-FDD-Band7

00:13:56

failed Test-IF4p5-TDD-Band40

00:48:09

passed Test-Mono-FDD-Band13

00:38:05

passed Test-Mono-FDD-Band7

01:13:08

passed Test-Mono-TDD-Band40

00:31:37