Clarify that an AndroidTest.xml file needs to be deleted for autogen warning to be meaningful

The previous wording confused a user.

Change-Id: I8342d631e6b19a175a436aa38031712b0f16d201
Bug: None
Test: None
diff --git a/tradefed/autogen.go b/tradefed/autogen.go
index 4ea8a0b..89c69bd 100644
--- a/tradefed/autogen.go
+++ b/tradefed/autogen.go
@@ -197,10 +197,10 @@
 		return autogenPath
 	}
 	if len(options.OptionsForAutogenerated) > 0 {
-		ctx.ModuleErrorf("Extra tradefed configurations (%v) were provided for an autogenerated xml file, but the autogenerated xml file was not used.", options.OptionsForAutogenerated)
+		ctx.ModuleErrorf("You likely need to delete your soong modules local AndroidTest.xml file.  Extra tradefed configurations (%v) were provided for an autogenerated xml file, but the autogenerated xml file was not used.", options.OptionsForAutogenerated)
 	}
 	if len(options.TestRunnerOptions) > 0 {
-		ctx.ModuleErrorf("Extra test runner options (%v) were provided for an autogenerated xml file, but the autogenerated xml file was not used.", options.TestRunnerOptions)
+		ctx.ModuleErrorf("You likely need to delete your soong modules local AndroidTest.xml file.  Extra test runner options (%v) were provided for an autogenerated xml file, but the autogenerated xml file was not used.", options.TestRunnerOptions)
 	}
 	return path
 }