How do I legally notify my HOA of my need for "reasonable accommodation" under the Fair Housing Act due to my asthma disability?

Respectfully, you have not mentioned the "reasonable accommodation" you seek. That is the first step. It appears you are not asking that an exception to the rules and regulations be made for you, due to your disability, but that you are requesting that the rules be changed for everyone because of your disability. That may be a deal breaker. The HOA is not required to alter the fundamental nature of their business model due to your disability.