Reland Add microdroid_16k

So far only non-protected VMs can boot with 16k kernel.

Support for microdroid_16k pvms is tracked in b/376870129.

Bug: 317201718
Bug: 376517173
Bug: 333730505
Bug: 376870129
Test: adb shell /apex/com.android.virt/bin/vm run-microdroid \
    --os microdroid_16k \
    --debug full
Test: atest MicrodropidTests
Test: atest MicrodroidHostTestCases
Test: atest virtualizationmanager_device_test
Test: presubmit
Change-Id: I0fe5cd431b16f57e5bcc51146691fd0368d30818
diff --git a/guest/kernel/Android.bp b/guest/kernel/Android.bp
index 8c6cccb..d3249f6 100644
--- a/guest/kernel/Android.bp
+++ b/guest/kernel/Android.bp
@@ -43,3 +43,12 @@
         default: [],
     }),
 }
+
+filegroup {
+    name: "microdroid_kernel_16k_prebuilt-arm64",
+    // Below are properties that are conditionally set depending on value of build flags.
+    srcs: select(release_flag("RELEASE_AVF_MICRODROID_KERNEL_VERSION"), {
+        "android15_66": ["android15-6.6/arm64/16k/kernel-6.6"],
+        default: [],
+    }),
+}