Enable compat checking & lint for module_lib api

These were previously turned off as there were no previous
releases to compare it to. Check in empty files as comparison.

The new tethering APIs fail lint -- I have filed a release
blocking bug to get these cleaned up.

Bug: 149430003
Bug: 147559833
Test: m module-lib-api-api-lint
Test: m module-lib-api-check-last-released-api (with+without incompatibilities)
Change-Id: I2b171dc836ca121502fb345d8dd512a05c566a49

StubLibraries.bp

@@ -197,20 +197,17 @@ droidstubs {
             api_file: "api/module-lib-current.txt",
             removed_api_file: "api/module-lib-removed.txt",
         },
-        // TODO(b/147559833) enable the compatibility check against the last release API
-        // and the API lint
-        //last_released: {
-        //    api_file: ":last-released-module-lib-api",
-        //    removed_api_file: "api/module-lib-removed.txt",
-        //    baseline_file: ":module-lib-api-incompatibilities-with-last-released"
-        //},
-        //api_lint: {
-        //    enabled: true,
-        //    new_since: ":last-released-module-lib-api",
-        //    baseline_file: "api/module-lib-lint-baseline.txt",
-        //},
+        last_released: {
+            api_file: ":last-released-module-lib-api",
+            removed_api_file: "api/module-lib-removed.txt",
+            baseline_file: ":module-lib-api-incompatibilities-with-last-released"
+        },
+        api_lint: {
+            enabled: true,
+            new_since: ":last-released-module-lib-api",
+            baseline_file: "api/module-lib-lint-baseline.txt",
+        },
     },
-    //jdiff_enabled: true,
 }