NR MIMO 2x2 Support Hooks in L2simulator

This commit provides CSI reporting support which is required for MIMO. It also updates the configuration files, provides sample BLER simualtion files for packet dropping in the MIMO 2x2 case. It also includes the hooks and functions (e.g., updating UCI2_3_4 PDU field) for MIMO 2x2 support. This commit will not include any channel abstraction code or modelling.

The provided BLER curves are used in the packet dropping abstraction process. They result from an exponential effective SINR mapping (EESM) and comparison to MATLAB link-level simulation models.

"Look-up tables of performance versus signal-to-noise ratio (SNR) are obtained via PHY simulations in additive white Gaussian noise (AWGN) channels. Then, to evaluate the BLER of fading channel, we map the received SINR to an AWGN curve using these look-up tables. Note that due to time/frequency selective fading, the received SINR value for each packet/ resource block varies. This requires the computation of AWGN equivalent SINR, also generally known as effective SINR, by mapping the individual symbol SINRs to a scalar. Then, the performance of the PHY in a fading channel at a given effective SINR is equivalent to the performance in AWGN channel."