kunit: Return void from kunit_run_all_tests()

No caller tests the return value of this function.

The integer return type is still a remnant from when the function
was executed as initcall. This usage however was removed in
commit 8c0d884986ba ("init: main: add KUnit to kernel init")

Link: https://lore.kernel.org/r/20260901-kunit-void-v1-1-c91952391d66@linutronix.de
Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Reviewed-by: David Gow <david@davidgow.net>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2 files changed