[vm tool] Introduce check-feature-enabled

Introduce this command to allow host to query feature (such as
com.android.kvm.LLPVM_CHANGES) is enabled on device. Implement this in
libavf_features, so that virtmrg can share code.

Bug: 325630143
Test: Inspect output of vm check-feature-enabled
com.android.kvm.LLPVM_CHANGES

Change-Id: I9f11f6d8a98e1df6926492edee2152908c770e73
diff --git a/libs/avf_features/Android.bp b/libs/avf_features/Android.bp
new file mode 100644
index 0000000..71f33db
--- /dev/null
+++ b/libs/avf_features/Android.bp
@@ -0,0 +1,26 @@
+package {
+    default_applicable_licenses: ["Android-Apache-2.0"],
+}
+
+rust_defaults {
+    name: "libavf_features.defaults",
+    crate_name: "avf_features",
+    defaults: ["avf_build_flags_rust"],
+    srcs: ["src/lib.rs"],
+    edition: "2021",
+    prefer_rlib: true,
+    rustlibs: [
+        "android.system.virtualizationservice-rust",
+        "libanyhow",
+        "liblog_rust",
+    ],
+}
+
+rust_library {
+    name: "libavf_features",
+    defaults: ["libavf_features.defaults"],
+    apex_available: [
+        "//apex_available:platform",
+        "com.android.virt",
+    ],
+}