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/include/configs/P1010RDB.h b/include/configs/P1010RDB.h
index 1152bca..344e19d 100644
--- a/include/configs/P1010RDB.h
+++ b/include/configs/P1010RDB.h
@@ -29,7 +29,7 @@
 #endif
 
 #ifdef CONFIG_SPIFLASH
-#ifdef CONFIG_SECURE_BOOT
+#ifdef CONFIG_NXP_ESBC
 #define CONFIG_RAMBOOT_SPIFLASH
 #define CONFIG_RESET_VECTOR_ADDRESS	0x110bfffc
 #else
@@ -50,7 +50,7 @@
 #endif
 
 #ifdef CONFIG_NAND
-#ifdef CONFIG_SECURE_BOOT
+#ifdef CONFIG_NXP_ESBC
 #define CONFIG_SPL_INIT_MINIMAL
 #define CONFIG_SPL_FLUSH_IMAGE
 #define CONFIG_SPL_TARGET		"u-boot-with-spl.bin"