arm-bsp: add new sbsa-ref machine

This is mostly based on the existing qemu-generic-arm64 machine, but by
not being based on the genericarm64 and instead being specifically a
machine to run on the qemu sbsa-ref machine we get to tune differently.

Specifically, this configures sbsa-ref to be a Neoverse N2 (v9), and the
tune is set to match.  Another notable difference to qemu-generic-arm64
is that the kernel configuration is at present defconfig.  We may wish
to change this in the future to be the same fragmented configuration as
genericarm64.

We have to ignore two testimage parselogs failures: one from NUMA which
will be fixed in a future EDK2 release, and one from efifb where we
should be using the bochsdrm driver instead (further investigation is
needed)

Signed-off-by: Ross Burton <ross.burton@arm.com>
Signed-off-by: Jon Mason <jon.mason@arm.com>

.gitlab-ci.yml

@@ -173,6 +173,16 @@ genericarm64:
 generic-arm64:
   extends: .build
 
+sbsa-ref:
+  extends: .build
+  parallel:
+    matrix:
+      - KERNEL: [linux-yocto, linux-yocto-rt]
+        TOOLCHAINS: [gcc, clang]
+        TESTING: testimage
+      - KERNEL: linux-yocto-dev
+        TESTING: testimage
+
 juno:
   extends: .build
   parallel: