Common testcase directories: Clean up duplicates

This CL addresses the problem that native tests build for multiple
architectures and also build for host.

First it restructures each testcase folder to the following layout:
<testcase>/<testcase>.config
<testcase>/<arch 1>/testcase
<testcase>/<arch 2>/testcase

Secondly it now uses the new soong-zip prefix capability to
separate out host and target testcases in the device-tests &
general-tests zip files.

Bug:36692141
Test: `make device-tests general-tests cts -j` &
      ensured all built successfully.

Change-Id: I4e8b084ee56fa8940914911649ff35507d87eb27
diff --git a/core/tasks/device-tests.mk b/core/tasks/device-tests.mk
index 731937f..299e160 100644
--- a/core/tasks/device-tests.mk
+++ b/core/tasks/device-tests.mk
@@ -21,7 +21,7 @@
 	sed -i -e 's/\s\+/\n/g' $@.list
 	grep $(HOST_OUT_TESTCASES) $@.list > $@-host.list || true
 	grep $(TARGET_OUT_TESTCASES) $@.list > $@-target.list || true
-	$(hide) $(SOONG_ZIP) -d -o $@ -C $(HOST_OUT) -l $@-host.list -C $(PRODUCT_OUT) -l $@-target.list
+	$(hide) $(SOONG_ZIP) -d -o $@ -P host -C $(HOST_OUT) -l $@-host.list -P target -C $(PRODUCT_OUT) -l $@-target.list
 
 device-tests: $(device-tests-zip)
 $(call dist-for-goals, device-tests, $(device-tests-zip))
diff --git a/core/tasks/general-tests.mk b/core/tasks/general-tests.mk
index e02faa7..9629bfa 100644
--- a/core/tasks/general-tests.mk
+++ b/core/tasks/general-tests.mk
@@ -20,7 +20,7 @@
 	sed -i -e 's/\s\+/\n/g' $@.list
 	grep $(HOST_OUT_TESTCASES) $@.list > $@-host.list || true
 	grep $(TARGET_OUT_TESTCASES) $@.list > $@-target.list || true
-	$(hide) $(SOONG_ZIP) -d -o $@ -C $(HOST_OUT) -l $@-host.list -C $(PRODUCT_OUT) -l $@-target.list
+	$(hide) $(SOONG_ZIP) -d -o $@ -P host -C $(HOST_OUT) -l $@-host.list -P target -C $(PRODUCT_OUT) -l $@-target.list
 
 general-tests: $(general-tests-zip)
 $(call dist-for-goals, general-tests, $(general-tests-zip))