selftests: kselftest: Treat xpass as successful result

The harness treats these tests as successful, as does pytest.

Align kselftest.h to the rest of the ecosystem.

None of the Linux selftests seem to actually use this anyways.

Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Link: https://lore.kernel.org/r/20260302-kselftest-harness-v2-1-3143aa41d989@linutronix.de
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>

Author: t-8ch

tools/testing/selftests/kselftest.h

@@ -399,6 +399,7 @@ static inline __noreturn void ksft_exit_fail(void)
 #define ksft_finished()			\
 	ksft_exit(ksft_plan ==		\
 		  ksft_cnt.ksft_pass +	\
+		  ksft_cnt.ksft_xpass +	\
 		  ksft_cnt.ksft_xfail +	\
 		  ksft_cnt.ksft_xskip)