This patch reverts changes made to `os.makedirs()` in Python 3.7.

Prior to Python 3.7, mode argument also affected newly-created
intermediate-level directories, and that was not the case for Python since
version 3.7 up to version 3.14 [1]. The reason was that with mode preventing
directory creating, the function fails after it creates the first
intermediate-level directory.

Since there is Solaris code that depends on the old behavior, this patch brings
it back. Note that we are not the only ones affected by this and so upstream
brought this functionality back in Python 3.15 but with a slightly different
semantics [2] [3].

The long term plan is to drop this patch entirely, however before we can do so
we need to make sure that all our `os.makedirs()` consumers either do not need
the old `os.makedirs()` behavior or are properly adapted to work with unpatched
Python 3.15+ (by adding the `parent_mode` parameter to their `os.makedirs()`
calls).

List of all our possible `os.makedirs()` consumers we need to evaluate:

illumos-gate - https://www.illumos.org/issues/18508
oi-userland - TODO
pkg5 - TODO
others ... - TODO

For reference:
[1] https://github.com/python/cpython/issues/64129
[2] https://github.com/python/cpython/issues/86533
[3] https://docs.python.org/3.15/library/os.html#os.makedirs

--- Python-3.15.2/Lib/os.py.orig
+++ Python-3.15.2/Lib/os.py
@@ -241,7 +241,7 @@
                 makedirs(head, mode=parent_mode, exist_ok=exist_ok,
                          parent_mode=parent_mode)
             else:
-                makedirs(head, exist_ok=exist_ok)
+                makedirs(head, mode, exist_ok)
         except FileExistsError:
             # Defeats race condition when another thread created the path
             pass
--- Python-3.15.2/Lib/test/test_os/test_os.py.orig
+++ Python-3.15.2/Lib/test/test_os/test_os.py
@@ -2153,12 +2153,12 @@
             base = os_helper.TESTFN
             parent = os.path.join(base, 'dir1')
             path = os.path.join(parent, 'dir2')
-            os.makedirs(path, 0o555)
+            os.makedirs(path, 0o755)
             self.assertTrue(os.path.exists(path))
             self.assertTrue(os.path.isdir(path))
             if os.name != 'nt':
-                self.assertEqual(os.stat(path).st_mode & 0o777, 0o555)
-                self.assertEqual(os.stat(parent).st_mode & 0o777, 0o775)
+                self.assertEqual(os.stat(path).st_mode & 0o777, 0o755)
+                self.assertEqual(os.stat(parent).st_mode & 0o777, 0o755)
 
     @unittest.skipIf(
         support.is_emscripten or support.is_wasi,