distro/rhel9: use azure-rhui pkg set and image config for vhd

Extract the non-RHUI specific package set and image configuration into a
common definitions, which will be used by both image types.

Redefine the package sets and default image configuration used by both
image types to inherit from a common definition.

Regenerate image manifests for RHEL-9 / c9s `vhd` and `azure-rhui`
images.

There is no change in the resulting manifest for the `azure-rhui` image
type. However there are substantial changes to the `vhd` image
definition, which is now almost identical to the `azure-rhui` image
type, to provide consistent experience regardless if using RHUI or not.

The default partition table used by the `vhd` image type has been kept
as it was before, since there is yet no consensus on what size to
standardize for both image types.

test/data/manifests/rhel_90-x86_64-azure_rhui-boot.json

@@ -13672,6 +13672,5 @@
         "checksum": "sha256:2cfbed0a9a51b8ab7e277f835d068e3df43c225034cb68a2c52580ee478316bc"
       }
     ]
-  },
-  "no-image-info": true
+  }
 }

test/data/manifests/rhel_91-x86_64-azure_rhui-boot.json

@@ -18995,6 +18995,5 @@
         "checksum": "sha256:2cfbed0a9a51b8ab7e277f835d068e3df43c225034cb68a2c52580ee478316bc"
       }
     ]
-  },
-  "no-image-info": true
+  }
 }