Since commit d8131c2965 ("kbuild: remove $(MODLIB)/source symlink"),
modules_install does not create the 'source' symlink.
Remove the stale code from builddeb and kernel.spec.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Most of the lines in the spec file are independent of any build
condition.
Split the body of the spec file into scripts/package/kernel.spec.
scripts/package/mkspec will prepend some env-dependent variables.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>