allwinner: psci: Invert check in .validate_ns_entrypoint

Checking the exceptional case and letting the success case fall through
is not only more idiomatic, but it also allows adding more exceptional
cases in the future, such as a check for overlapping secure DRAM.

Change-Id: I720441a6a8853fd7f211ebe851f14d921a6db03d
Signed-off-by: Samuel Holland <samuel@sholland.org>
diff --git a/plat/allwinner/common/sunxi_pm.c b/plat/allwinner/common/sunxi_pm.c
index e70d859..aa80c52 100644
--- a/plat/allwinner/common/sunxi_pm.c
+++ b/plat/allwinner/common/sunxi_pm.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2017-2020, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2017-2021, ARM Limited and Contributors. All rights reserved.
  *
  * SPDX-License-Identifier: BSD-3-Clause
  */
@@ -207,10 +207,11 @@
 static int sunxi_validate_ns_entrypoint(uintptr_t ns_entrypoint)
 {
 	/* The non-secure entry point must be in DRAM */
-	if (ns_entrypoint >= SUNXI_DRAM_BASE)
-		return PSCI_E_SUCCESS;
+	if (ns_entrypoint < SUNXI_DRAM_BASE) {
+		return PSCI_E_INVALID_ADDRESS;
+	}
 
-	return PSCI_E_INVALID_ADDRESS;
+	return PSCI_E_SUCCESS;
 }
 
 static void sunxi_get_sys_suspend_power_state(psci_power_state_t *req_state)