allwinner: security: Fix SPC guard

The "#ifdef SUNXI_SPC_BASE" guard was meant to allow the build on SoCs
without a Secure Peripherals Controller, so that we skip that part of
the security setup. But in the current position this will trigger a
warning about an unused variable.

Simply move the guard one line up to cover the variable as well.
Signed-off-by: Andre Przywara <andre.przywara@arm.com>

plat/allwinner/common/sunxi_security.c

@@ -25,9 +25,9 @@
  */
 void sunxi_security_setup(void)
 {
+#ifdef SUNXI_SPC_BASE
 	int i;
 
-#ifdef SUNXI_SPC_BASE
 	INFO("Configuring SPC Controller\n");
 	/* SPC setup: set all devices to non-secure */
 	for (i = 0; i < 6; i++)