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##### SUMMARY
When i collect facts from TrueNAS, with the command : `ansible truenas -m setup | grep "ansible_distribution"`
the variable "ansible_distribution_major_version" is missing.
When i use same command on debian host, the variable is stell here

##### ISSUE TYPE
- Bug Report

##### COMPONENT NAME
lib/ansible/module_utils/facts

##### ANSIBLE VERSION
```
ansible 2.10.2
  config file = /srv/ansible/ansible.cfg
  configured module search path = ['/srv/ansible/library']
  ansible python module location = /srv/ansible-venv/lib/python3.7/site-packages/ansible
  executable location = /srv/ansible-venv/bin/ansible
  python version = 3.7.3 (default, Dec 20 2019, 18:57:59) [GCC 8.3.0]
```

##### CONFIGURATION
<!--- Paste verbatim output from "" between quotes -->
```
ANSIBLE_FORCE_COLOR(/srv/ansible/ansible.cfg) = True
DEFAULT_HOST_LIST(/srv/ansible/ansible.cfg) = ['/srv/ansible/site.host']
DEFAULT_JINJA2_EXTENSIONS(/srv/ansible/ansible.cfg) = jinja2.ext.do
DEFAULT_MANAGED_STR(/srv/ansible/ansible.cfg) = Gestion par Ansible: {file} modifie le %Y-%m-%d %H:%M:%S par {uid} depuis {host}
DEFAULT_MODULE_PATH(/srv/ansible/ansible.cfg) = ['/srv/ansible/library']
DEFAULT_ROLES_PATH(/srv/ansible/ansible.cfg) = ['/srv/ansible/roles']
DEFAULT_STDOUT_CALLBACK(/srv/ansible/ansible.cfg) = yaml
DISPLAY_SKIPPED_HOSTS(/srv/ansible/ansible.cfg) = False
INTERPRETER_PYTHON(/srv/ansible/ansible.cfg) = auto_silent
RETRY_FILES_ENABLED(/srv/ansible/ansible.cfg) = False

```

##### OS / ENVIRONMENT
<!--- Provide all relevant information below, e.g. target OS versions, network device firmware, etc. -->


##### STEPS TO REPRODUCE
ansible truenas -m setup | grep "ansible_distribution"

##### EXPECTED RESULTS
```
...
        "ansible_distribution": "FreeBSD",
        "ansible_distribution_release": "12.2-RC3",
        "ansible_distribution_major_version": "12",
        "ansible_distribution_version": "FreeBSD 12.2-RC3 7c4ec6ff02c(HEAD) TRUENAS",
...
```


##### ACTUAL RESULTS
```
...
        "ansible_distribution": "FreeBSD",
        "ansible_distribution_release": "12.2-RC3",
        "ansible_distribution_version": "FreeBSD 12.2-RC3 7c4ec6ff02c(HEAD) TRUENAS",
...
```

netbsd_facts = {}
        platform_release = platform.release()
        netbsd_facts['distribution_release'] = platform_release
        rc, out, dummy = self.module.run_command("/sbin/sysctl -n kern.version")
        match = re.match(r'NetBSD\s(\d+)\.(\d+)\s\((GENERIC)\).*', out)
        if match:
            netbsd_facts['distribution_major_version'] = match.group(1)
            netbsd_facts['distribution_version'] = '%s.%s' % match.groups()[:2]
        else:
            netbsd_facts['distribution_major_version'] = platform_release.split('.')[0]
            netbsd_facts['distribution_version'] = platform_release
        return netbsd_facts
    def get_distribution_SMGL(self):
        smgl_facts = {}
        smgl_facts['distribution'] = 'Source Mage GNU/Linux'
        return smgl_facts
    def get_distribution_SunOS(self):
        sunos_facts = {}
        data = get_file_content('/etc/release').splitlines()[0]
        if 'Solaris' in data:
            
            uname_r = get_uname(self.module, flags=['-r'])
            ora_prefix = ''
            if 'Oracle Solaris' in data:
                data = data.replace('Oracle ', '')
                ora_prefix = 'Oracle '