Add Zephyr manifest file (west.yml)

Extend this repository to be a Zephyr application manifest-module
to better support development as a downstream Zephyr module when
using `west`.

Verified by using `west init -m $repo --mr $branch $workspace` to
initialize a west workspace, followed by a west update and a
successful build of `$mcuboot/boot/zephyr` for mimxrt1064_evk.
Further verified that the following testcases still pass with
mcuboot options on twister:
  mcuboot/boot/zephyr
  zephyr/tests/subsys/dfu
  zephyr/samples/subsys/mgmt/mcumgr/smp_svr

Signed-off-by: Gregory SHUE <[email protected]>

Author: legrand-gregshue

west.yml

@@ -0,0 +1,31 @@
+# SPDX-License-Identifier: Apache-2.0
+# Copyright (c) 2022 Legrand North America, LLC.
+
+# The west manifest file for Zephyr ecosystem development.
+#
+# Usage:
+# west init -m https://github.com/mcu-tools/mcuboot
+# west update
+
+manifest:
+  version: "0.12"
+
+  remotes:
+    - name: zephyrproject
+      url-base: https://github.com/zephyrproject-rtos
+    - name: mcu-tools
+      url-base: https://github.com/mcu-tools
+
+  defaults:
+    remote: mcu-tools
+
+  projects:
+    - name: zephyr
+      revision: main
+      remote: zephyrproject
+      import:
+        name-blocklist:
+          - mcuboot
+
+  self:
+    path: mcuboot