inspired by accepted (but not yet merged) PR to include the
(unique_)byte_buffer_t for MAC/PHY interfacing, this patch adds
a few more useful bits to that. Buffer management for UL data is now
done in MAC and only a pointer to the data is passed in the UL action.
* Move Tx softbuffer to MAC (until UL HARQ class is ready)
* Remove temparal data member in cc_worker
* Remove memcpy after packing MAC PDU
* Refactor NR resource allocation classes. Use DCI instead of grant for dummy PDSCH UE/eNB test
* Minor refactors in NR workers and ue_dl
* Fix include issues
* fix compilation issues