machine/corstone1000: Add Cortex‑A320 support

Enable the Corstone‑1000 Cortex‑A320 variant by:

- Introduce `machine/include/corstone1000-a320.inc` to configure the
  default Ethos‑U MAC count when `cortexa320` is in MACHINE_FEATURES,
  and allow override via `ETHOSU_NUM_MACS`.
- Add a KAS profile at `kas/corstone1000-a320.yml` for Cortex‑A320
  FVP-based builds.
- Extend corstone1000.inc to detect MACHINE_FEATURES (cortexa320) and
  pull in the matching tune-<core>.inc (default still Cortex-A35).
- Add the `meta-ethos` layer as a dependency of `meta-arm-bsp` for
  Cortex‑A320 builds and define a new KMachine override to pull in
  the Ethos‑U driver recipe.
- In `conf/machine/corstone1000-fvp.conf`, inspect `MACHINE_FEATURES`
  and set `FVP_EXE` to `FVP_Corstone-1000_with_Cortex-A320` when
  `cortexa320` is enabled, otherwise fall back to `FVP_Corstone-1000`.
- In `recipes-devtools/fvp/fvp-corstone1000.bb`, add a
  `SRC_URI:cortexa320` entry (with checksums) for the Cortex‑A320 FVP
  build archive.
- Disable the rootfs CPIO file compression so it is not compressed
  twice when bundled with the kernel

Signed-off-by: Michael Safwat <michael.safwat@arm.com>
Signed-off-by: Frazer Carsley <frazer.carsley@arm.com>
Signed-off-by: Hugues KAMBA MPIANA <hugues.kambampiana@arm.com>
Signed-off-by: Jon Mason <jon.mason@arm.com>

meta-arm-bsp/recipes-kernel/linux/files/corstone1000/defconfig

@@ -122,3 +122,4 @@ CONFIG_EXT4_FS=y
 # CONFIG_EXT4_FS_POSIX_ACL is not set
 # CONFIG_EXT4_FS_SECURITY is not set
 # CONFIG_EXT4_DEBUG is not set
+CONFIG_INITRAMFS_COMPRESSION_NONE=y