deb: Move deb manifest to its own subdir

This is a part of a refactor that will split the package manager
code so that it's possible to use other package managers in other
layers.

(From OE-Core rev: f8ee8bc737a982001b9fd0ad441495a52f12e9b4)

Signed-off-by: Fredrik Gustafsson <fredrigu@axis.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

meta/lib/oe/manifest.py

@@ -187,32 +187,13 @@ class Manifest(object, metaclass=ABCMeta):
 
         return installed_pkgs
 
-class DpkgManifest(Manifest):
-    def create_initial(self):
-        with open(self.initial_manifest, "w+") as manifest:
-            manifest.write(self.initial_manifest_file_header)
-
-            for var in self.var_maps[self.manifest_type]:
-                pkg_list = self.d.getVar(var)
-
-                if pkg_list is None:
-                    continue
-
-                for pkg in pkg_list.split():
-                    manifest.write("%s,%s\n" %
-                                   (self.var_maps[self.manifest_type][var], pkg))
-
-    def create_final(self):
-        pass
-
-    def create_full(self, pm):
-        pass
 
 
 def create_manifest(d, final_manifest=False, manifest_dir=None,
                     manifest_type=Manifest.MANIFEST_TYPE_IMAGE):
     from oe.package_manager.rpm.manifest import RpmManifest
     from oe.package_manager.ipk.manifest import OpkgManifest
+    from oe.package_manager.deb.manifest import DpkgManifest
     manifest_map = {'rpm': RpmManifest,
                     'ipk': OpkgManifest,
                     'deb': DpkgManifest}

meta/lib/oe/package_manager/deb/__init__.py

@@ -0,0 +1,3 @@
+#
+# SPDX-License-Identifier: GPL-2.0-only
+#

meta/lib/oe/package_manager/deb/manifest.py

@@ -0,0 +1,26 @@
+#
+# SPDX-License-Identifier: GPL-2.0-only
+#
+
+from oe.manifest import Manifest
+
+class DpkgManifest(Manifest):
+    def create_initial(self):
+        with open(self.initial_manifest, "w+") as manifest:
+            manifest.write(self.initial_manifest_file_header)
+
+            for var in self.var_maps[self.manifest_type]:
+                pkg_list = self.d.getVar(var)
+
+                if pkg_list is None:
+                    continue
+
+                for pkg in pkg_list.split():
+                    manifest.write("%s,%s\n" %
+                                   (self.var_maps[self.manifest_type][var], pkg))
+
+    def create_final(self):
+        pass
+
+    def create_full(self, pm):
+        pass

meta/lib/oe/rootfs.py

@@ -13,6 +13,7 @@ import subprocess
 import re
 from oe.package_manager.rpm.manifest import RpmManifest
 from oe.package_manager.ipk.manifest import OpkgManifest
+from oe.package_manager.deb.manifest import DpkgManifest
 
 class Rootfs(object, metaclass=ABCMeta):
     """