Kconfig: Enable FIT_SIGNATURE if ARM64

Enabling FIT_SIGNATURE required the old authentication method to be
disabled so disable this for K3 SOCs and enable FIT_SIGNATURE for K3
Platforms.

Signed-off-by: Kamlesh Gurudasani <kamlesh@ti.com>
[ cleanup the patch ]
Signed-off-by: Manorit Chawdhry <m-chawdhry@ti.com>
diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index 3045698..bdd535f 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -799,6 +799,7 @@
 	select SUPPORT_SPL
 	select FIT
 	select REGEX
+	select FIT_SIGNATURE if ARM64
 
 config ARCH_OMAP2PLUS
 	bool "TI OMAP2+"
diff --git a/boot/Kconfig b/boot/Kconfig
index b424265..e8fb03b 100644
--- a/boot/Kconfig
+++ b/boot/Kconfig
@@ -125,8 +125,7 @@
 config FIT_IMAGE_POST_PROCESS
 	bool "Enable post-processing of FIT artifacts after loading by U-Boot"
 	depends on FIT
-	depends on TI_SECURE_DEVICE || SOCFPGA_SECURE_VAB_AUTH
-	default y if TI_SECURE_DEVICE
+	depends on SOCFPGA_SECURE_VAB_AUTH
 	help
 	  Allows doing any sort of manipulation to blobs after they got extracted
 	  from FIT images like stripping off headers or modifying the size of the