Add `rocksdb_fifo_compaction_options_set_allow_compaction()` to C API bindings ("c.h")

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### Expected behavior
I want use rocksdb in a C project, so I include c.h,
I need the FIFO comapction style with light compaction, just as the WIKI suggested.
BUT I CAN NOT FIND THE C API IN C.H TO TURN THIS ON.

### Actual behavior
No API in c.h to turn this on.

### Steps to reproduce the behavior