arm: add support to corstone1000 platform

Corstone1000 is a platform from arm, which includes pre
verified Corstone SSE710 sub-system that combines Cortex-A and
Cortex-M processors [0].

This code adds the support for the Cortex-A35 implementation
at host side, it contains also the necessary bits to support
the Corstone 1000 FVP (Fixed Virtual Platform) [1] and also the
FPGA MPS3 board implementation of this platform. [2]

0: https://developer.arm.com/documentation/102360/0000
1: https://developer.arm.com/tools-and-software/open-source-software/arm-platforms-software/arm-ecosystem-fvps
2: https://developer.arm.com/documentation/dai0550/c/

Signed-off-by: Rui Miguel Silva <rui.silva@linaro.org>
Reviewed-by: Tom Rini <trini@konsulko.com>
diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index c618aad..95f9253 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -1352,6 +1352,12 @@
 	select ENV_IS_IN_FLASH if MTD
 	imply DISTRO_DEFAULTS
 
+config TARGET_CORSTONE1000
+	bool "Support Corstone1000 Platform"
+	select ARM64
+	select PL01X_SERIAL
+	select DM
+
 config TARGET_TOTAL_COMPUTE
 	bool "Support Total Compute Platform"
 	select ARM64
@@ -2300,7 +2306,7 @@
 source "arch/arm/mach-npcm/Kconfig"
 
 source "board/armltd/total_compute/Kconfig"
-
+source "board/armltd/corstone1000/Kconfig"
 source "board/bosch/shc/Kconfig"
 source "board/bosch/guardian/Kconfig"
 source "board/Marvell/octeontx/Kconfig"