tools: Use soong_ui instead of make

Switch to soong_ui to dump make variables, which ensures a consistent
parser for the product makefiles, and may provide other benefits, like
sandboxed executions.

Use soong_ui rather than the legacy make startup wrapper, which just
calls soong_ui. This allows us to automatically set the parallelism if
-j is omitted, so remove the default here and let soong_ui choose an
appropriate value for your machine.

Test: art/tools/golem/build-target.sh --machine-type=android-armv8
Test: art/tools/golem/build-target.sh --machine-type=android-armv8 --golem=art-opt-cc
Change-Id: I39c838b7198658534f6cadc64159f59b3ffdd38c
1 file changed