Set the option to repo

def _set_repo_option(repo, option):
    '''
    Set the option to repo
    '''
    if not option:
        return
    opt = option.split('=')
    if len(opt) != 2:
        return
    if opt[0] == 'trusted':
        repo['trusted'] = opt[1] == 'yes'
    else:
        repo[opt[0]] = opt[1]