selftests: check before install

When the test cases is not supported by the current architecture
the install files(TEST_PROGS, TEST_PROGS_EXTENDED and TEST_FILES)
will be empty. Check it before installation to dismiss a failure
reported by install program.
Signed-off-by: NBamvor Jian Zhang <bamvor.zhangjian@linaro.org>
Signed-off-by: NShuah Khan <shuahkh@osg.samsung.com>

tools/testing/selftests/Makefile

@@ -72,7 +72,6 @@ ifdef INSTALL_PATH
 	@# Ask all targets to install their files
 	mkdir -p $(INSTALL_PATH)
 	for TARGET in $(TARGETS); do \
-		mkdir -p $(INSTALL_PATH)/$$TARGET ; \
 		make -C $$TARGET INSTALL_PATH=$(INSTALL_PATH)/$$TARGET install; \
 	done;
 

tools/testing/selftests/lib.mk

@@ -12,11 +12,14 @@ run_tests: all
 	$(RUN_TESTS)
 
 define INSTALL_RULE
-	mkdir -p $(INSTALL_PATH)
-	@for TEST_DIR in $(TEST_DIRS); do\
+	@if [ "X$(TEST_PROGS)$(TEST_PROGS_EXTENDED)$(TEST_FILES)" != "X" ]; then			\
+		mkdir -p $(INSTALL_PATH);								\
+		for TEST_DIR in $(TEST_DIRS); do							\
 			cp -r $$TEST_DIR $(INSTALL_PATH);						\
-	done;
-	install -t $(INSTALL_PATH) $(TEST_PROGS) $(TEST_PROGS_EXTENDED) $(TEST_FILES)
+		done;											\
+		echo "install -t $(INSTALL_PATH) $(TEST_PROGS) $(TEST_PROGS_EXTENDED) $(TEST_FILES)";	\
+		install -t $(INSTALL_PATH) $(TEST_PROGS) $(TEST_PROGS_EXTENDED) $(TEST_FILES);		\
+	fi
 endef
 
 install: all