##### SUMMARY
<!--- Explain the problem briefly below -->
The settings in `ANSIBLE_SSH_ARGS` are not applied to any host created with `add_host` resulting in incorrect connection to those hosts.
##### ISSUE TYPE
- Bug Report

##### COMPONENT NAME
<!--- Write the short name of the module, plugin, task or feature below, use your best guess if unsure -->
`lib/ansible/plugins/connection/ssh.py`
##### ANSIBLE VERSION
<!--- Paste verbatim output from "ansible --version" between quotes -->
```paste below
ansible 2.11.0.dev0
  config file = /Users/sdoran/.ansible.cfg
  configured module search path = ['/usr/local/share/ansible/library']
  ansible python module location = /Users/sdoran/Source/ansible/lib/ansible
  ansible collection location = /Users/sdoran/.ansible/collections:/usr/local/share/ansible/collections
  executable location = /Users/sdoran/Source/ansible/bin/ansible
  python version = 3.8.2 (default, May 12 2020, 12:11:39) [Clang 11.0.3 (clang-1103.0.32.59)]

```

##### CONFIGURATION
<!--- Paste verbatim output from "ansible-config dump --only-changed" between quotes -->
```paste below
DEFAULT_LOG_PATH(env: ANSIBLE_LOG_PATH) = /Users/sdoran/.ansible/ansible.log
DEFAULT_VAULT_PASSWORD_FILE(env: ANSIBLE_VAULT_PASSWORD_FILE) = /Users/sdoran/bin/getvaultkey.sh
DEVEL_WARNING(env: ANSIBLE_DEVEL_WARNING) = False
```

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


##### STEPS TO REPRODUCE
<!--- Describe exactly how to reproduce the problem, using a minimal test-case -->
Run the following playbook passing `ANSIBLE_SSH_ARGS` as an environment variable

```
env ANSIBLE_SSH_ARGS='-o UserKnownHostsFile=/dev/null' ansible-playbook playbook.yml -vvv
```
<!--- Paste example playbooks or commands between quotes below -->
```yaml
- hosts: localhost
  gather_facts: no
  tasks:
    - add_host:
        name: delegatetome
        ansible_host: 127.0.0.1

- name: Play against added host
  hosts: delegatetome
  tasks:
    - ping:
```

<!--- HINT: You can paste gist.github.com links for larger files -->

##### EXPECTED RESULTS
`ANSIBLE_SSH_ARGS` are applied to the host created with `add_host` and used during connection.
<!--- Describe what you expected to happen when running the steps above -->
(output truncated)
```
...
PLAY [Play against added host] ****************************************************************************************

TASK [Gathering Facts] ************************************************************************************************
<127.0.0.1> SSH: EXEC ssh -o UserKnownHostsFile=/dev/null -o StrictHostKeyChecking=no -o...
...
```

##### ACTUAL RESULTS
Missing `ANSIBLE_SSH_ARGS`.
```paste below
...
PLAY [Play against added host] ****************************************************************************************
META: ran handlers

TASK [ping] ***********************************************************************************************************
task path: /Users/sdoran/Projects/Vagrant/Ansible Lab/test-local.yml:16
<127.0.0.1> ESTABLISH SSH CONNECTION FOR USER: None
<127.0.0.1> SSH: EXEC ssh -C -o ControlMaster=auto -o ControlPersist=60s...
...
```

self.sshpass_pipe = os.pipe()
                        cmd[1] = b'-d' + to_bytes(self.sshpass_pipe[0], nonstring='simplerepr', errors='surrogate_or_strict')
                    display.vvv(u"RETRYING BECAUSE OF CONTROLPERSIST BROKEN PIPE")
                    return_tuple = func(self, *args, **kwargs)
                remaining_retries = remaining_tries - attempt - 1
                _handle_error(remaining_retries, cmd[0], return_tuple, self._play_context.no_log, self.host)
                break
            
            except AnsibleAuthenticationFailure:
                
                raise
            except (AnsibleConnectionFailure, Exception) as e:
                if attempt == remaining_tries - 1:
                    raise
                else:
                    pause = 2 ** attempt - 1
                    if pause > 30:
                        pause = 30
                    if isinstance(e, AnsibleConnectionFailure):
                        msg = u"ssh_retry: attempt: %d, ssh return code is 255. cmd (%s), pausing for %d seconds" % (attempt + 1, cmd_summary, pause)
                    else:
                        msg = (u"ssh_retry: attempt: %d, caught exception(%s) from cmd (%s), "
                               u"pausing for %d seconds" % (attempt + 1, to_text(e), cmd_summary, pause))
                    display.vv(msg, host=self.host)
                    time.sleep(pause)
                    continue
        return return_tuple
    return wrapped
class Connection(ConnectionBase):