freescale/powerpc: Rename the config CONFIG_SECURE_BOOT name

Rename the CONFIG_SECURE_BOOT name to CONFIG_NXP_ESBC to avoid
conflicts 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/arch/powerpc/cpu/mpc85xx/Kconfig b/arch/powerpc/cpu/mpc85xx/Kconfig
index c038a6d..8cc82f8 100644
--- a/arch/powerpc/cpu/mpc85xx/Kconfig
+++ b/arch/powerpc/cpu/mpc85xx/Kconfig
@@ -1208,8 +1208,8 @@
 	help
 		Use Freescale common code for Local Access Window
 
-config SECURE_BOOT
-	bool	"Secure Boot"
+config NXP_ESBC
+	bool	"NXP_ESBC"
 	help
 		Enable Freescale Secure Boot feature. Normally selected
 		by defconfig. If unsure, do not change.