test: Update trust setting for remaining test YAMLs

The YAMLs in ./test/hack enumerated the images to pull with
content trust. All images in the 'linuxkit' org should
now have trust enabled.

Signed-off-by: Rolf Neugebauer <rolf.neugebauer@docker.com>

test/hack/test-ltp.yml

@@ -16,8 +16,5 @@ files:
   - path: /etc/ltp/baseline
     contents: "100"
 trust:
-  image:
-    - linuxkit/kernel
-    - linuxkit/init
-    - linuxkit/runc
-    - linuxkit/containerd
+  org:
+    - linuxkit

test/hack/test.yml

@@ -17,9 +17,5 @@ onboot:
     image: linuxkit/poweroff:f9a0a5e52fd2a97908bda33db2afffafe4a6a67d
     command: ["/bin/sh", "/poweroff.sh", "3"]
 trust:
-  image:
-    - linuxkit/kernel
-    - linuxkit/init
-    - linuxkit/runc
-    - linuxkit/containerd
-    - linuxkit/dhcpcd
+  org:
+    - linuxkit