ima_setup.sh: Fix signed policy requirement check

tst_require_kconfigs() quits testing with tst_brk TCONF, but that first
hides the explanation in ima_conditionals.sh (which also calls tst_brk
TCONF) but also quits testing in ima_policy.sh (which calls tst_res
TCONF). Therefore use tst_check_kconfigs binary instead.

Fixes: c38b528 ("ima_{conditionals, policy}: Handle policy required to be signed")
Link: https://lore.kernel.org/ltp/20260128125852.37411-1-pvorel@suse.cz/
Reported-by: Mimi Zohar <zohar@linux.ibm.com>
Tested-by: Mimi Zohar <zohar@linux.ibm.com>
Signed-off-by: Petr Vorel <pvorel@suse.cz>

Author: pevik

testcases/kernel/security/integrity/ima/tests/ima_setup.sh

@@ -469,7 +469,7 @@ require_evmctl()
 # d958083a8f640 ("x86/ima: define arch_get_ima_policy() for x86") # v5.0
 check_need_signed_policy()
 {
-	tst_secureboot_enabled && tst_kvcmp -ge '6.5' && tst_require_kconfigs \
+	tst_secureboot_enabled && tst_kvcmp -ge '6.5' && tst_check_kconfigs \
 		'CONFIG_IMA_KEYRINGS_PERMIT_SIGNED_BY_BUILTIN_OR_SECONDARY,CONFIG_IMA_ARCH_POLICY'
 }