KVM: selftests: arm64: Correct feature test for S1PIE in get-reg-list

The ID register for S1PIE is ID_AA64MMFR3_EL1.S1PIE which is bits 11:8 but
get-reg-list uses a shift of 4, checking SCTLRX instead. Use a shift of 8
instead.

Fixes: 5f0419a008 ("KVM: selftests: get-reg-list: add Permission Indirection registers")
Signed-off-by: Mark Brown <broonie@kernel.org>
Reviewed-by: Joey Gouly <joey.gouly@arm.com>
Link: https://lore.kernel.org/r/20240731-kvm-arm64-fix-s1pie-test-v1-1-a9253f3b7db4@kernel.org
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>

tools/testing/selftests/kvm/aarch64/get-reg-list.c

@@ -32,13 +32,13 @@ static struct feature_id_reg feat_id_regs[] = {
 	{
 		ARM64_SYS_REG(3, 0, 10, 2, 2),	/* PIRE0_EL1 */
 		ARM64_SYS_REG(3, 0, 0, 7, 3),	/* ID_AA64MMFR3_EL1 */
-		4,
+		8,
 		1
 	},
 	{
 		ARM64_SYS_REG(3, 0, 10, 2, 3),	/* PIR_EL1 */
 		ARM64_SYS_REG(3, 0, 0, 7, 3),	/* ID_AA64MMFR3_EL1 */
-		4,
+		8,
 		1
 	}
 };