Use F1 internally: F1 Setup

Description

Use F1 Setup Request/Response internally, and follow F1 spec by creating the CellGroupConfig always at the DU, and sending the UE Capabilities from CU down to DU. This enables to use MIMO, 256 QAM, etc, in F1 (and monolithic, of course).

Changes:

• Use F1 Setup Req/Resp internally even in monolithic
• Move from MAC to RRC:
  • ServingCellConfigCommon
  • ServingCellConfigDedicated
  • MIB
  • SIB1
  • additional minor stuff
• Fix some memory leaks in RRC; fix memory leaks in MAC
• Simplify CU configuration (no SCC, no DU radio parameters; will stop if present)

Planned work:

• Correctly initialize SIB1 with the PLMN (OAI UE connects anyway)
• @Cedric.Roux I yet have to apply your suggestion to prevent concurrent initialization of F1
• handle multiple slices to be transported in F1

Work planned to be done after this MR:

• Remove the "remote address" of the CU
• Handle multiple slices to be transported in F1
• Send NGAP Setup Request only after having received the F1 Setup Request