erts: Add BIFs processes_first/0 and processes_next/1
#18356
| Job | Run time |
|---|---|
| 6m 19s | |
| 4s | |
| 5m 9s | |
| 8m 9s | |
| 3m 47s | |
| 4m 52s | |
| 9m 36s | |
| 8m 51s | |
| 6m 55s | |
| 14m 51s | |
| 5m 28s | |
| 17m 40s | |
| 4m 10s | |
| 1h 7m 13s | |
| 4m 36s | |
| 0s | |
| 8m 11s | |
| 2h 55m 51s |