!SIB1 is not correctly filled! This commit does not work with COTS UEs!
The next commit fixes this.

- Move radio config (e.g., minRXTXTIME, SIB1 TDA, do_SRS, etc) down to
  MAC.
- Some parameters in MAC are redundant: delete them.
- Remove call to nr_mac_config_scc() from RRC and simulators, the MAC
  initialization routine calls it implicitly