Update pylint to v2.9.3 and fix the new issues it spots (#946)

In CI run against pylint 2.9.3 and fix occurrences of:
 - W0237 (arguments-renamed)
 - W0402 (deprecated-module)

The W0402 deprecated-module was about module `imp`:

    cloudinit/patcher.py:9: [W0402(deprecated-module), ]
        Uses of a deprecated module 'imp'

The imp module is deprecated and replaced by importlib, which according
to the documentation has no replacement for acquire_lock() and
release_lock(), which are the only reason why `imp` is imported.
    
Nothing about the code using this lock that actually requires it.
Let's remove the locking code and the import altogether.

Dropping the locking makes patcher.patch() an empty wrapper around
_patch_logging(). Rename _patch_logging() to patch_logging() and
call it directly instead. Drop patch().

1 files changed, 4 insertions, 4 deletions

diff --git a/cloudinit/distros/rhel.py b/cloudinit/distros/rhel.py
index be5b3d24..c9ee2747 100644
--- a/cloudinit/distros/rhel.py
+++ b/cloudinit/distros/rhel.py
@@ -78,18 +78,18 @@ class Distro(distros.Distro):
         }
         rhel_util.update_sysconfig_file(out_fn, locale_cfg)
 
-    def _write_hostname(self, hostname, out_fn):
+    def _write_hostname(self, hostname, filename):
         # systemd will never update previous-hostname for us, so
         # we need to do it ourselves
-        if self.uses_systemd() and out_fn.endswith('/previous-hostname'):
-            util.write_file(out_fn, hostname)
+        if self.uses_systemd() and filename.endswith('/previous-hostname'):
+            util.write_file(filename, hostname)
         elif self.uses_systemd():
             subp.subp(['hostnamectl', 'set-hostname', str(hostname)])
         else:
             host_cfg = {
                 'HOSTNAME': hostname,
             }
-            rhel_util.update_sysconfig_file(out_fn, host_cfg)
+            rhel_util.update_sysconfig_file(filename, host_cfg)
 
     def _read_system_hostname(self):
         if self.uses_systemd():