The TEST_DIRS was introduced in Commit 
e8c1d7cdf137 ("selftests: copy
TEST_DIRS to INSTALL_PATH") for coping a whole directory in ftrace.
After rsync(with -a) is introduced by Commit 
900d65ee11aa ("selftests:
change install command to rsync"). Rsync could handle the directory
without the definition of TEST_DIRS.
This patch simply replace TEST_DIRS with TEST_FILES in ftrace and remove
the TEST_DIRS in tools/testing/selftest/lib.mk
Acked-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Bamvor Jian Zhang <bamvor.zhangjian@linaro.org>
Signed-off-by: Shuah Khan <shuahkh@osg.samsung.com>
 all:
 
 TEST_PROGS := ftracetest
-TEST_DIRS := test.d
+TEST_FILES := test.d
 
 include ../lib.mk
 
 
 define INSTALL_RULE
        @if [ "X$(TEST_PROGS)$(TEST_PROGS_EXTENDED)$(TEST_FILES)" != "X" ]; then                                        \
                mkdir -p ${INSTALL_PATH};                                                                               \
-               echo "rsync -a $(TEST_DIRS) $(TEST_PROGS) $(TEST_PROGS_EXTENDED) $(TEST_FILES) $(INSTALL_PATH)/";       \
-               rsync -a $(TEST_DIRS) $(TEST_PROGS) $(TEST_PROGS_EXTENDED) $(TEST_FILES) $(INSTALL_PATH)/;              \
+               echo "rsync -a $(TEST_PROGS) $(TEST_PROGS_EXTENDED) $(TEST_FILES) $(INSTALL_PATH)/";    \
+               rsync -a $(TEST_PROGS) $(TEST_PROGS_EXTENDED) $(TEST_FILES) $(INSTALL_PATH)/;           \
        fi
        @if [ "X$(TEST_GEN_PROGS)$(TEST_GEN_PROGS_EXTENDED)$(TEST_GEN_FILES)" != "X" ]; then                                    \
                mkdir -p ${INSTALL_PATH};                                                                               \