kselftest/arm64: parse POE_MAGIC in a signal frame

Teach the signal frame parsing about the new POE frame, avoids warning when it
is generated.
Signed-off-by: Joey Gouly <joey.gouly@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Mark Brown <broonie@kernel.org>
Cc: Shuah Khan <shuah@kernel.org>
Reviewed-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20240822151113.1479789-29-joey.gouly@arm.comSigned-off-by: Will Deacon <will@kernel.org>

tools/testing/selftests/arm64/signal/testcases/testcases.c

@@ -161,6 +161,10 @@ bool validate_reserved(ucontext_t *uc, size_t resv_sz, char **err)
 			if (head->size != sizeof(struct esr_context))
 				*err = "Bad size for esr_context";
 			break;
+		case POE_MAGIC:
+			if (head->size != sizeof(struct poe_context))
+				*err = "Bad size for poe_context";
+			break;
 		case TPIDR2_MAGIC:
 			if (head->size != sizeof(struct tpidr2_context))
 				*err = "Bad size for tpidr2_context";