arm-bsp/corstone1000-a320: Drop meta-ethos dependency

Corstone1000 with Cortex A320 now uses the in-tree ethosu driver, so the
external meta-ethos layer (and its meta-sca dependency) is no longer needed.

Remove meta-ethos and meta-sca from the Corstone-1000 A320 kas
config, drop the layer dependency on meta-ethos, and stop
installing arm-npu-ethosu. Update the Corstone-1000
change log to reflect the removed layers.

Signed-off-by: Michael Safwat <michael.safwat@arm.com>
Signed-off-by: Jon Mason <jon.mason@arm.com>

kas/corstone1000-a320.yml

@@ -7,11 +7,3 @@ local_conf_header:
   a320: |
     MACHINE_FEATURES += "cortexa320"
     OVERRIDES .= ":cortexa320"
-
-repos:
-  meta-ethos:
-    url: https://gitlab.arm.com/iot/meta-ethos.git
-    branch: whinlatter
-  meta-sca:
-    url: https://github.com/priv-kweihmann/meta-sca.git
-    branch: master