vmbase_example: Condition compilation for aarch64

This change is a preparation for porting libvmbase_example to x86_64 platform. All dependencies that are arm specific are moved to separate section.

Bug: 362733888
Test: m libvmbase_example*
Flag: EXEMPT bugfix
Change-Id: Ib8d54cc4573dce8ed408ed61031b7267659b578a
diff --git a/guest/vmbase_example/Android.bp b/guest/vmbase_example/Android.bp
index 30d72bd..1cee848 100644
--- a/guest/vmbase_example/Android.bp
+++ b/guest/vmbase_example/Android.bp
@@ -8,7 +8,6 @@
     crate_name: "vmbase_example",
     srcs: ["src/main.rs"],
     rustlibs: [
-        "libaarch64_paging",
         "libdiced_open_dice_nostd",
         "liblibfdt_nostd",
         "liblog_rust_nostd",
@@ -16,6 +15,13 @@
         "libvirtio_drivers",
         "libvmbase",
     ],
+    target: {
+        android_arm64: {
+            rustlibs: [
+                "libaarch64_paging",
+            ],
+        },
+    },
 }
 
 genrule {