imx: ele_ahab: use hextoul

Use hextoul which looks a bit simpler.

Signed-off-by: Peng Fan <peng.fan@nxp.com>
diff --git a/arch/arm/mach-imx/ele_ahab.c b/arch/arm/mach-imx/ele_ahab.c
index 9bb3791..5f23486 100644
--- a/arch/arm/mach-imx/ele_ahab.c
+++ b/arch/arm/mach-imx/ele_ahab.c
@@ -402,7 +402,7 @@
 	if (argc < 2)
 		return CMD_RET_USAGE;
 
-	addr = simple_strtoul(argv[1], NULL, 16);
+	addr = hextoul(argv[1], NULL);
 
 	printf("Authenticate OS container at 0x%lx\n", addr);