It is not a case of converting your status from asylum applicant to permit holder for family reasons. They are two separate processes. As you are married to a German, you have a legal entitlement to a permit according to paragraph 28 of the Residence Act.
Paragraph 10 of the Residence Act deals with the question of issuing permits to people who are in the asylum process. It states that where a person has a legal entitlement to a permit, it is to be issued before the end of the asylum case. There are others situations where this is complicated but not for someone who is the spouse of a German.
It is up to you whether you then decide to let your asylum case proceed or withdraw it. You should consider the likelihood of being given a refugee status and whether this provides certain advantages (e.g. regarding family reunification) over a residence permit as the spouse of a German.