kbuild: mkspec - fix build rpm

This is patch to fix incorrect mkspec script to make rpm correctly at 2.6.27 vanilla kernel.
This is regression in 2.6.27. 2.6.26 make rpm work good.
In 2.6.27 'make rpm' say error from rpmbuild "Many unpacked files (*.fw)."

Signed-off-by: Evgeniy Manachkin <sfstudio@mail.ru>
Acked-by: Alan Cox <alan@redhat.com>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Cc: Stable <stable@kernel.org>