MLECO-3183: Refactoring application sources

Platform agnostic application sources are moved into application
api module with their own independent CMake projects.

Changes for MLECO-3080 also included - they create CMake projects
individial API's (again, platform agnostic) that dependent on the
common logic. The API for KWS_API "joint" API has been removed and
now the use case relies on individual KWS, and ASR API libraries.

Change-Id: I1f7748dc767abb3904634a04e0991b74ac7b756d
Signed-off-by: Kshitij Sisodia <kshitij.sisodia@arm.com>
diff --git a/source/use_case/object_detection/usecase.cmake b/source/use_case/object_detection/usecase.cmake
index 42c4f2c..850e7fc 100644
--- a/source/use_case/object_detection/usecase.cmake
+++ b/source/use_case/object_detection/usecase.cmake
@@ -14,6 +14,8 @@
 #  See the License for the specific language governing permissions and
 #  limitations under the License.
 #----------------------------------------------------------------------------
+# Append the API to use for this use case
+list(APPEND ${use_case}_API_LIST "object_detection")
 
 USER_OPTION(${use_case}_FILE_PATH "Directory with custom image files to use, or path to a single image, in the evaluation application"
     ${CMAKE_CURRENT_SOURCE_DIR}/resources/${use_case}/samples/