Use MCUboot tagged version

Pick up a tagged version of MCUboot which contains all
features which are required for next TF-M release (v1.2).

Signed-off-by: Tamas Ban <tamas.ban@arm.com>

Change-Id: Icbcc033ca680c235e890e154723a26c15f99c406
diff --git a/tf-m-cppcheck.yaml b/tf-m-cppcheck.yaml
index e82548f..f011ebc 100644
--- a/tf-m-cppcheck.yaml
+++ b/tf-m-cppcheck.yaml
@@ -57,8 +57,11 @@
           default: 'https://git.trustedfirmware.org/mirror/mbed-tls.git'
       - string:
           name: 'MCUBOOT_REFSPEC'
-          default: 'refs/heads/master'
-#         default: 'refs/tags/v1.6.0'
+          default: 'refs/tags/TF-Mv1.2-integ'
+          description: |
+            Specify which MCUboot version to use
+            refs/heads/master    : Pick up latest master
+            refs/tags/<TAG_NAME> : Pick up a tagged version
       - string:
           name: 'MCUBOOT_URL'
           default: 'https://git.trustedfirmware.org/mirror/mcuboot.git'