kbuild: do not create intermediate *.tar for tar packages
Commit
05e96e96a315 ("kbuild: use git-archive for source package
creation") split the compression as a separate step to factor out
the common build rules.
With the previous commit, we got back to the situation where source
tarballs are compressed on-the-fly.
There is no reason to keep the separate compression rules.
Generate the comressed tar packages directly.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nathan Chancellor <nathan@kernel.org>