[PATCH for-next v3] selftests/cpufreq: gitignore output files and clean them in make clean

[Li Zhijian <lizhijian@xxxxxxxxxxx>]

After `make run_tests`, the git status complains:
Untracked files:
    (use "git add <file>..." to include in what will be committed)
        cpufreq/cpufreq_selftest.dmesg_cpufreq.txt
        cpufreq/cpufreq_selftest.dmesg_full.txt
        cpufreq/cpufreq_selftest.txt

Cc: "Rafael J. Wysocki" <rafael@xxxxxxxxxx>
Cc: Viresh Kumar <viresh.kumar@xxxxxxxxxx>
Cc: Shuah Khan <shuah@xxxxxxxxxx>
Signed-off-by: Li Zhijian <lizhijian@xxxxxxxxxxx>
---
Cc: linux-pm@xxxxxxxxxxxxxxx
---
Hello,
Cover letter is here.

This patch set aims to make 'git status' clear after 'make' and 'make
run_tests' for kselftests.
---
V3:
  add Copyright descirption
V2:
  split as a separate patch from a small one [0]
  [0] https://lore.kernel.org/linux-kselftest/20241015010817.453539-1-lizhijian@xxxxxxxxxxx/

Signed-off-by: Li Zhijian <lizhijian@xxxxxxxxxxx>
---
 tools/testing/selftests/cpufreq/.gitignore | 2 ++
 tools/testing/selftests/cpufreq/Makefile   | 1 +
 2 files changed, 3 insertions(+)
 create mode 100644 tools/testing/selftests/cpufreq/.gitignore

diff --git a/tools/testing/selftests/cpufreq/.gitignore b/tools/testing/selftests/cpufreq/.gitignore
new file mode 100644
index 000000000000..67604e91e068
--- /dev/null
+++ b/tools/testing/selftests/cpufreq/.gitignore
@@ -0,0 +1,2 @@
+# SPDX-License-Identifier: GPL-2.0-only
+cpufreq_selftest.*
diff --git a/tools/testing/selftests/cpufreq/Makefile b/tools/testing/selftests/cpufreq/Makefile
index c86ca8342222..9b2ccb10b0cf 100644
--- a/tools/testing/selftests/cpufreq/Makefile
+++ b/tools/testing/selftests/cpufreq/Makefile
@@ -3,6 +3,7 @@ all:
 
 TEST_PROGS := main.sh
 TEST_FILES := cpu.sh cpufreq.sh governor.sh module.sh special-tests.sh
+EXTRA_CLEAN := cpufreq_selftest.dmesg_cpufreq.txt cpufreq_selftest.dmesg_full.txt cpufreq_selftest.txt
 
 include ../lib.mk
 
-- 
2.44.0