[Tests] Make would fail with no device error without GPUs (#2909)

* Fix make failed with no device error without GPUs

* Add DISCOVERY_MODE PRE_TEST option in gtest_discover_tests so  test binary will execute during runtime to discover the tests before actually running them

* Set DISCOVERY_MODE to PRE_TEST in gtest_discover_tests() so test binary will execute during runtime to discover the tests before actually running them

* Remove duplicated DISCOVERY_MODE option

test/gtest/CMakeLists.txt

@@ -28,9 +28,9 @@ function(add_gtest TEST_NAME TEST_CPP)
   if(NOT MIOPEN_EMBED_DB STREQUAL "")
       target_link_libraries(${TEST_NAME} $<BUILD_INTERFACE:miopen_data>)
   endif()
-  if(NOT WIN32) # TODO: cannot run on Windows due to missing DLL dependencies
+  if(NOT WIN32 AND MIOPEN_TEST_DISCRETE) # TODO: cannot run on Windows due to missing DLL dependencies
     # Enable CMake to discover the test binary
-    gtest_discover_tests(${TEST_NAME} DISCOVERY_TIMEOUT 300 PROPERTIES ENVIRONMENT "MIOPEN_USER_DB_PATH=${CMAKE_CURRENT_BINARY_DIR};MIOPEN_TEST_FLOAT_ARG=${MIOPEN_TEST_FLOAT_ARG};MIOPEN_TEST_ALL=${MIOPEN_TEST_ALL};MIOPEN_TEST_MLIR=${MIOPEN_TEST_MLIR};MIOPEN_TEST_COMPOSABLEKERNEL=${MIOPEN_TEST_COMPOSABLEKERNEL};CODECOV_TEST=${CODECOV_TEST};MIOPEN_TEST_DBSYNC=${MIOPEN_TEST_DBSYNC};MIOPEN_TEST_CONV=${MIOPEN_TEST_CONV};MIOPEN_TEST_DEEPBENCH=${MIOPEN_TEST_DEEPBENCH};MIOPEN_DEBUG_TUNING_ITERATIONS_MAX=${MIOPEN_DEBUG_TUNING_ITERATIONS_MAX}")
+    gtest_discover_tests(${TEST_NAME} DISCOVERY_TIMEOUT 300 DISCOVERY_MODE PRE_TEST PROPERTIES ENVIRONMENT "MIOPEN_USER_DB_PATH=${CMAKE_CURRENT_BINARY_DIR};MIOPEN_TEST_FLOAT_ARG=${MIOPEN_TEST_FLOAT_ARG};MIOPEN_TEST_ALL=${MIOPEN_TEST_ALL};MIOPEN_TEST_MLIR=${MIOPEN_TEST_MLIR};MIOPEN_TEST_COMPOSABLEKERNEL=${MIOPEN_TEST_COMPOSABLEKERNEL};CODECOV_TEST=${CODECOV_TEST};MIOPEN_TEST_DBSYNC=${MIOPEN_TEST_DBSYNC};MIOPEN_TEST_CONV=${MIOPEN_TEST_CONV};MIOPEN_TEST_DEEPBENCH=${MIOPEN_TEST_DEEPBENCH};MIOPEN_DEBUG_TUNING_ITERATIONS_MAX=${MIOPEN_DEBUG_TUNING_ITERATIONS_MAX}")
   endif()
     target_link_libraries(${TEST_NAME} BZip2::BZip2)
   if(WIN32)