Please note that this will rewrite history and anyone else that is working off of an old copy of the origin's develop branch will need to update in a similar fashion. Otherwise things will get very sloppy.
# Delete your local develop
git checkout master
git branch -D develop
# Recreate your local develop, based on origin's master
git pull origin master
git checkout -b develop
# Push and overwrite the sloppy develop on the origin
git push origin develop --force