Revert "Experimanetal change in dlsch_channel_commensation_TM34. Will not work for more than 2 antennas."

This reverts commit cbd30e62.

This reverts commit 83324945, reversing
changes made to cbd30e62.

Testing.

Changing names of output files in dlsim respectiively.

Conflicts:
	openair1/PHY/TOOLS/cdot_prod.c
	targets/PROJECTS/GENERIC-LTE-EPC/CONF/enb.band7.usrpb210.conf

1. Fixing a bug in dlsch_channel_level_TM56.
avg128D = _mm_setzero_si128() must be done inside the rx_antennas loop and not before

2. Cleaning up code in dlsch_demodulation.c

3. Offsets for TM5 and TM6 still must be validated.

4. Right now IA and I-UA receivers for TM4 have the same offset -
validate if any additional penalty/gain is needed.

5. Shortened file names in dlsim.c since matlab can read only 63-characters file names.

6. Tested: TM4 U2 -gS perfect CE works fine for EESM and MIESM abstraction (MCS 4 MSE= 0.007 dB on both streams).

Validating mcs-dependent shift.

Passing 2 avrage channel lvel and not max how it was done before.
Continuing with calibration.

TM4 and verify if any additional gain/penatly is needed.

Going back to fixed shift in log2_approx for TM4. Playing with computing the channel average in order to find optimal shift.

2.Fixing shift LUT for TM1. Mcs 21, 26 and 28 show erroneous performance. (see attachement in commit)