bug#72116: 30.0.60; Filling c-ts-mode documentation is broken

[Damien Cassou]

Filling documentation in a c-ts-mode buffer doesn't insert the " * "
prefix. It works fine in c-mode. How to reproduce:

1. Install the C treesitter grammar
2. Start emacs with "emacs -Q"
3. Open the attached file in a new buffer
4. Run M-x c-ts-mode
5. Move point to the middle of line 2
6. Press M-q

Expected: 2 lines of documentation, each one starting with " * "

Actual: 2 lines of documentation, only the first one starting
with " * "

If you remove step 4 from the above instructions, c-mode will do the
work just fine.

The solution to this bug could help solve bug#71760.

-- 
Damien Cassou

"Success is the ability to go from one failure to another without
losing enthusiasm." --Winston Churchill

foo.c
Description: Text document