### Summary

Ansible no longer returns distribution facts for my Amazon Linux 2 instances after #73767.

### Issue Type

Bug Report

### Component Name

setup

### Ansible Version

```console (paste below)
$ ansible --version
ansible [core 2.11.0b2.post0]  (detached HEAD 30c465c1a9) last updated 2021/03/17 18:53:46 (GMT -400)
  config file = /home/ec2-user/ansible-aws-coll/ansible/ansible.cfg
  configured module search path = ['/home/ec2-user/.ansible/plugins/modules', '/usr/share/ansible/plugins/modules']
  ansible python module location = /home/ec2-user/tmp/ansible/lib/ansible
  ansible collection location = /home/ec2-user/ansible-aws-coll/ansible/collections
  executable location = /home/ec2-user/tmp/ansible/bin/ansible
  python version = 3.8.5 (default, Feb 18 2021, 01:24:20) [GCC 7.3.1 20180712 (Red Hat 7.3.1-12)]
  jinja version = 2.11.3
  libyaml = True
```


### Configuration

```console (paste below)
$ ansible-config dump --only-changed
DEVEL_WARNING(env: ANSIBLE_DEVEL_WARNING) = False
```


### OS / Environment

Amazon Linux 2

### Steps to Reproduce

```
ansible localhost -m setup | grep distribution
```


### Expected Results

With 78d3810fdf:
```
[WARNING]: No inventory was parsed, only implicit localhost is available
        "ansible_distribution": "Amazon",
        "ansible_distribution_file_parsed": true,
        "ansible_distribution_file_path": "/etc/system-release",
        "ansible_distribution_file_variety": "Amazon",
        "ansible_distribution_major_version": "2",
        "ansible_distribution_release": "NA",
        "ansible_distribution_version": "2",
```

### Actual Results

```console (paste below)
[WARNING]: No inventory was parsed, only implicit localhost is available
```

dist = (get_distribution(), get_distribution_version(), get_distribution_codename())
        distribution_guess = {
            'distribution': dist[0] or 'NA',
            'distribution_version': dist[1] or 'NA',
            
            'distribution_release': 'NA' if dist[2] is None else dist[2]
        }
        distribution_guess['distribution_major_version'] = distribution_guess['distribution_version'].split('.')[0] or 'NA'
        return distribution_guess
    def process_dist_files(self):
        
        
        dist_file_facts = {}
        dist_guess = self._guess_distribution()
        dist_file_facts.update(dist_guess)
        for ddict in self.OSDIST_LIST:
            name = ddict['name']
            path = ddict['path']
            allow_empty = ddict.get('allowempty', False)
            has_dist_file, dist_file_content = self._get_dist_file_content(path, allow_empty=allow_empty)
            
            
            if has_dist_file and allow_empty:
                dist_file_facts['distribution'] = name