fix elxr arm kernel issue

Author: srmungar

config/osv/wind-river-elxr/elxr12/imageconfigs/defaultconfigs/default-raw-aarch64.yml

@@ -92,4 +92,4 @@ systemConfig:
     cmdline: "quiet splash console=ttyS0,115200 console=tty0 loglevel=7"
     uki: true
     packages:
-     - linux-image-arm64-signed-template
+     - linux-image-cloud-arm64 

image-templates/elxr12-aarch64-minimal-raw.yml

@@ -30,7 +30,7 @@ disk:
       mountOptions: umask=0077
 
     - id: rootfs
-      type: linux-root-arm64-signed-template
+      type: linux-root-arm64
       start: 513MiB
       end: "0"
       fsType: ext4