kthread_create_on_cpu() always requires format string to contain one
'%u' at the end, as it automatically adds the CPU ID when passing it
to kthread_create_on_node(). The former doesn't marked as __printf()
as it's not printf-like itself, which effectively hides this from
the compiler.
If you convert this function to printf-like, you'll see the following:

In file included from drivers/firmware/psci/psci_checker.c:15:
drivers/firmware/psci/psci_checker.c: In function 'suspend_tests':
drivers/firmware/psci/psci_checker.c:401:48: warning: too many 
arguments for format [-Wformat-extra-args]
     401 |                                                
"psci_suspend_test");
         |                                                
^~~~~~~~~~~~~~~~~~~
drivers/firmware/psci/psci_checker.c:400:32: warning: data argument not 
used by format string [-Wformat-extra-args]
     400 |                                                (void 
*)(long)cpu, cpu,
         |                                                              
     ^
     401 |                                                
"psci_suspend_test");
         |                                                
~~~~~~~~~~~~~~~~~~~

Add the missing format literal to fix this. Now the corresponding
kthread will be named as "psci_suspend_test-<cpuid>", as it's meant by
kthread_create_on_cpu().

Reported-by: kernel test robot <redacted>
Closes: 
https://lore.kernel.org/oe-kbuild-all/202408141012.KhvKaxoh-lkp@intel.com (local)
Closes: 
https://lore.kernel.org/oe-kbuild-all/202408141243.eQiEOQQe-lkp@intel.com (local)
Fixes: ea8b1c4a6019 ("drivers: psci: PSCI checker module")
Cc: stable@vger.kernel.org # 4.10+
Signed-off-by: Alexander Lobakin <aleksander.lobakin@intel.com>
---
 drivers/firmware/psci/psci_checker.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/firmware/psci/psci_checker.c 

b/drivers/firmware/psci/psci_checker.c
index 116eb465cdb4..ecc511c745ce 100644

--- a/drivers/firmware/psci/psci_checker.c
+++ b/drivers/firmware/psci/psci_checker.c

@@ -398,7 +398,7 @@ static int suspend_tests(void)

 		thread = kthread_create_on_cpu(suspend_test_thread,
 					       (void *)(long)cpu, cpu,
-					       "psci_suspend_test");
+					       "psci_suspend_test-%u");
 		if (IS_ERR(thread))
 			pr_err("Failed to create kthread on CPU %d\n", cpu);
 		else

-- 
2.46.0