Came in here knowing there'll be no info regarding "Chocobo Companion Skill Point Reset". Was not disappointed.
Maybe you should go read the post on the lodestone?

Chocobo Level Cap
For chocobos that have already attained the maximum rank, rewarding them with a Thavnairian onion following training will increase this upper limit by one.
* A Thavnairian onion is required each time you wish to raise the maximum rank.
* Chocobo companions cannot exceed rank 20.