Feature/zephyr ztest (#118)

* Leverage (older) embedded unit tests into external unit tests build upon copy of Zephyr's ztest library and CMake.

* Expand top-level CMake build to run external unit tests.

* Expand Zephyr module extension to run external unit tests via west or sanitycheck.

Co-authored-by: Gregory Shue <gregory.shue@legrand.us>

test/bacnet/wp/CMakeLists.txt

@@ -0,0 +1,45 @@
+# SPDX-License-Identifier: MIT
+
+cmake_minimum_required(VERSION 3.10 FATAL_ERROR)
+
+get_filename_component(basename ${CMAKE_CURRENT_SOURCE_DIR} NAME)
+project(test_${basename}
+	VERSION 1.0.0
+	LANGUAGES C)
+
+
+string(REGEX REPLACE "/bacnet/[a-zA-Z_/-]*$" "" TST_DIR ${CMAKE_CURRENT_SOURCE_DIR})
+set(ZTST_DIR "${TST_DIR}/ztest/src")
+string(REGEX REPLACE "/test$" "/src" SRC_DIR ${TST_DIR})
+
+add_compile_definitions(
+	BIG_ENDIAN=0
+	CONFIG_ZTEST=1
+	BACAPP_ALL
+	)
+
+include_directories(
+	${SRC_DIR}
+	${TST_DIR}/ztest/include
+	)
+
+add_executable(${PROJECT_NAME}
+    # File(s) under test
+	${SRC_DIR}/bacnet/wp.c
+    # Support files and stubs (pathname alphabetical)
+	${SRC_DIR}/bacnet/bacapp.c
+	${SRC_DIR}/bacnet/bacdcode.c
+	${SRC_DIR}/bacnet/bacdevobjpropref.c
+	${SRC_DIR}/bacnet/bacint.c
+	${SRC_DIR}/bacnet/bacreal.c
+	${SRC_DIR}/bacnet/bacstr.c
+	${SRC_DIR}/bacnet/bactext.c
+	${SRC_DIR}/bacnet/basic/sys/bigend.c
+	${SRC_DIR}/bacnet/datetime.c
+	${SRC_DIR}/bacnet/lighting.c
+	${SRC_DIR}/bacnet/indtext.c
+    # Test and test library files
+	./src/main.c
+	${ZTST_DIR}/ztest_mock.c
+	${ZTST_DIR}/ztest.c
+	)