Define Soong phony rules in Make am: c3d87d3112

Original change: https://android-review.googlesource.com/c/platform/build/soong/+/1325397

Change-Id: Ia6a1f96c75c660525127c25472327dd78ba58124

java/java.go

@@ -2874,11 +2874,7 @@ func (ks *kytheExtractJavaSingleton) GenerateBuildActions(ctx android.SingletonC
 	})
 	// TODO(asmundak): perhaps emit a rule to output a warning if there were no xrefTargets
 	if len(xrefTargets) > 0 {
-		ctx.Build(pctx, android.BuildParams{
-			Rule:   blueprint.Phony,
-			Output: android.PathForPhony(ctx, "xref_java"),
-			Inputs: xrefTargets,
-		})
+		ctx.Phony("xref_java", xrefTargets...)
 	}
 }