Remove the single-cell limit in F1 Setup Request processing and
refactor to loop-based cell handling. Move cell validation (PLMN
check, neighbor configuration validation, system info extraction),
cell creation, SIB encoding, and neighbor labeling inside a loop
over all available cells.
Update F1 Setup Response to include all cells instead of hardcoding to 1.
Add warning log when more than one cell is received. Add proper
cleanup with free_f1ap_setup_response() on error paths.
Impact:
- F1 Setup now accepts and processes multiple cells from a single
DU, enabling multi-cell deployments
- All cells are validated, created, and included in the setup
response