armv8: psci: skip setup code if we are not EL3

If we are running in EL2 skip PSCI implementation setup. This avoids an
exception if CONFIG_ARMV8_PSCI is set, but u-boot is started by TF-A.

Signed-off-by: Michael Walle <michael@walle.cc>
Reviewed-by: Priyanka Jain <priyanka.jain@nxp.com>

arch/arm/cpu/armv8/cpu.c

@@ -79,6 +79,9 @@ static void relocate_secure_section(void)
 
 void armv8_setup_psci(void)
 {
+	if (current_el() != 3)
+		return;
+
 	relocate_secure_section();
 	secure_ram_addr(psci_setup_vectors)();
 	secure_ram_addr(psci_arch_init)();