freescale/layerscape: Rename the config CONFIG_SECURE_BOOT name

Rename CONFIG_SECURE_BOOT to CONFIG_NXP_ESBC to avoid conflict
with UEFI secure boot.

Signed-off-by: Udit Agarwal <udit.agarwal@nxp.com>
Signed-off-by: Priyanka Jain <priyanka.jain@nxp.com>
diff --git a/board/freescale/ls1046aqds/ls1046aqds.c b/board/freescale/ls1046aqds/ls1046aqds.c
index b71c174..6a51dcd 100644
--- a/board/freescale/ls1046aqds/ls1046aqds.c
+++ b/board/freescale/ls1046aqds/ls1046aqds.c
@@ -407,7 +407,7 @@
 	ppa_init();
 #endif
 
-#ifdef CONFIG_SECURE_BOOT
+#ifdef CONFIG_NXP_ESBC
 	/*
 	 * In case of Secure Boot, the IBR configures the SMMU
 	 * to allow only Secure transactions.