external/iptables: use local-generated-sources-dir

local-intermediates-dir doesn't work for multiarch builds, because
each architecture needs a separate intermediates dir.  Use
local-generated-sources-dir, which gives a directory under $OUT/gen
that can be shared by both architectures.  Files installed into
$OUT/gen/*/*_intermediates and listed in LOCAL_GENERATED_SOURCES
will be copied into $OUT/obj*/*/*_intermediates automatically as
necessary.

Change-Id: I78e7898147a0e2303e814e8b93f7cd0edbd2914e
1 file changed