[OE-core] Avoid race condition between do_unpack and do_deploy_archives in archiver.bbclass

[Clemens Lang]

Hi,

the following patch fixes a race condition in archiver.bbclass that can
occur when a very specific set of preconditions is fulfilled:
 - a recipe sets $S to a directory that will be created by do_unpack
 - $B is at its default value of $S
 - the license of the recipe is in COPYLEFT_LICENSE_EXCLUDE, skipping
   source code archiving
When this happens, do_deploy_archives (which is a no-op task that only
prints a single line) does not depend indirectly on do_unpack, as it
would usually do via a dependency on
  do_ar_${@d.getVarFlag('ARCHIVER_MODE', 'src', True)}.
Because do_deploy_archives does not specify a working directory, it
defaults to $B, which does not exist when do_deploy_archives is run in
parallel (or before) do_unpack.

The attached patch fixes this by making do_deploy_archives run after
do_unpack in all cases (which is already does for recipes not excluded
due their license).

This problem is also present on dizzy (and thus probably also on fido).