Infineon: Add cyw20829 platform, shared slot feature, json memory map, psoc6 xip

Based in 1.8.0 release of MCUBoot library

This commit adds CYW20829 Infineon platform support with following capabilities:
1. Overwrite and swap upgrade mode support
2. Multi-image with up to 4 images
3. Hardware security counter is supported for CYW20829 platform

Add XIP support for PSOC6 platform - place BOOT slot in external memory and execute it in place using SMIF in XIP mode

and some new features for Infineon devices.

1. Shared upgrade slot feature - use one shared area for upgrade slots of multiple images
2. Memory map defined using JSON file - define memory regions for bootloader and user app in conventional way using JSON file
diff --git a/boot/bootutil/src/image_ed25519.c b/boot/bootutil/src/image_ed25519.c
index 940c18d..b5838c4 100644
--- a/boot/bootutil/src/image_ed25519.c
+++ b/boot/bootutil/src/image_ed25519.c
@@ -2,6 +2,7 @@
  * SPDX-License-Identifier: Apache-2.0
  *
  * Copyright (c) 2019 JUUL Labs
+ * Copyright (c) 2021 Arm Limited
  */
 
 #include <string.h>
@@ -15,6 +16,7 @@
 #include "mbedtls/asn1.h"
 
 #include "bootutil_priv.h"
+#include "bootutil/crypto/common.h"
 
 static const uint8_t ed25519_pubkey_oid[] = MBEDTLS_OID_ISO_IDENTIFIED_ORG "\x65\x70";
 #define NUM_ED25519_BYTES 32
@@ -43,8 +45,8 @@
         return -2;
     }
 
-    if (alg.len != sizeof(ed25519_pubkey_oid) - 1 ||
-        memcmp(alg.p, ed25519_pubkey_oid, sizeof(ed25519_pubkey_oid) - 1)) {
+    if (alg.MBEDTLS_CONTEXT_MEMBER(len) != sizeof(ed25519_pubkey_oid) - 1 ||
+        memcmp(alg.MBEDTLS_CONTEXT_MEMBER(p), ed25519_pubkey_oid, sizeof(ed25519_pubkey_oid) - 1)) {
         return -3;
     }