Replace annotation_processors with plugins

The annotation_processors property is deprecated, replace it with
plugins, and use java_plugin for modules that provide annotation
processors.

Bug: 77284273
Test: m checkbuild
Change-Id: I14ed4d81e097510866cbb9a27c72be4426117885
diff --git a/tools/processors/unsupportedappusage/Android.bp b/tools/processors/unsupportedappusage/Android.bp
index 1aca3ed..0e33fdd 100644
--- a/tools/processors/unsupportedappusage/Android.bp
+++ b/tools/processors/unsupportedappusage/Android.bp
@@ -1,6 +1,8 @@
 
-java_library_host {
+java_plugin {
     name: "unsupportedappusage-annotation-processor",
+    processor_class: "android.processor.unsupportedappusage.UnsupportedAppUsageProcessor",
+
     java_resources: [
         "META-INF/**/*",
     ],