doc: add instructions to build with ninja #152
| Job | Run time |
|---|---|
| 18m 26s | |
| 13m 44s | |
| 13m 27s | |
| 20m 15s | |
| 12m 59s | |
| 18m 13s | |
| 19m 26s | |
| 19m 25s | |
| 17m 47s | |
| 20m 45s | |
| 17m 1s | |
| 12m 35s | |
| 19m 11s | |
| 18m 47s | |
| 18m 26s | |
| 19m 23s | |
| 19m 38s | |
| 13m 42s | |
| 15m 20s | |
| 14m 36s | |
| 14m 17s | |
| 18m 38s | |
| 19m 45s | |
| 19m 4s | |
| 6h 54m 50s |