python3: update to 3.8.1

Drop backports, rebase other patches.

0001-main.c-if-OEPYTHON3HOME-is-set-use-instead-of-PYTHON.patch
is removed as the use case (allowing python 2 and 3 to coexist
in SDKs) is no longer relevant with Python 2.x reaching end of line
and upstream has refactored the code making a rebase difficult.
If needed, please re-add the patch to py2, rather than py3.

Python 3.8 no longer adds "m" to "3.8" in paths, so adjust the recipes
and classes accordingly.

The manifest for the 3.8.0 version is updated; particularly pkgutil
module is now packaged in -core (as other things in core need it);
this also necessitates allowing empty -pkgutil package to avoid
breakage across layers.

(From OE-Core rev: e6ab9f16b92aa1abdae82c535c1a452a1341b0e2)

Signed-off-by: Alexander Kanavin <alex.kanavin@gmail.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

meta/recipes-devtools/python/python3/avoid_warning_about_tkinter.patch

@@ -1,4 +1,4 @@
-From fead48c8b501a8d7c3db21df2e599f90f38f11d3 Mon Sep 17 00:00:00 2001
+From ba7202700578d435b07cfdfb7b57e83185752800 Mon Sep 17 00:00:00 2001
 From: Andrei Gherzan <andrei@gherzan.ro>
 Date: Mon, 28 Jan 2019 15:57:54 +0000
 Subject: [PATCH] _tkinter module needs tk module along with tcl. tk is not yet
@@ -11,26 +11,21 @@ Also simply disable the tk module since its not in DEPENDS.
 Signed-off-by: Andrei Gherzan <andrei@gherzan.ro>
 
 ---
- setup.py | 8 +++++---
- 1 file changed, 5 insertions(+), 3 deletions(-)
+ setup.py | 4 ++--
+ 1 file changed, 2 insertions(+), 2 deletions(-)
 
 diff --git a/setup.py b/setup.py
-index fbec00d..b7a36a6 100644
+index ab18ff0..7691258 100644
 --- a/setup.py
 +++ b/setup.py
-@@ -1623,10 +1623,12 @@ class PyBuildExt(build_ext):
-         self.extensions.extend(exts)
+@@ -1706,8 +1706,8 @@ class PyBuildExt(build_ext):
+         self.detect_decimal()
+         self.detect_ctypes()
+         self.detect_multiprocessing()
+-        if not self.detect_tkinter():
+-            self.missing.append('_tkinter')
++#        if not self.detect_tkinter():
++#            self.missing.append('_tkinter')
+         self.detect_uuid()
  
-         # Call the method for detecting whether _tkinter can be compiled
--        self.detect_tkinter(inc_dirs, lib_dirs)
-+        # self.detect_tkinter(inc_dirs, lib_dirs)
- 
--        if '_tkinter' not in [e.name for e in self.extensions]:
--            missing.append('_tkinter')
-+        # tkinter module will not be avalaible as yocto
-+        # doesn't have tk integrated (yet)
-+        #if '_tkinter' not in [e.name for e in self.extensions]:
-+        #    missing.append('_tkinter')
- 
-         # Build the _uuid module if possible
-         uuid_incs = find_file("uuid.h", inc_dirs, ["/usr/include/uuid"])
+ ##         # Uncomment these lines if you want to play with xxmodule.c