android.el: Make android-uninstall-app not reinstall

- uninstall, rather than reinstalling the app
- Fix reference to argument

Change-Id: I66afe170c1d0ce2e5acfccf7a0c635fd07764f32
diff --git a/files/android.el b/files/android.el
index 49f2f1e..5c66218 100644
--- a/files/android.el
+++ b/files/android.el
@@ -101,7 +101,7 @@
   (interactive
    (list
     (read-from-minibuffer "Package: ")))
-  (compile (format "adb install -r %s" package)))
+  (compile (format "adb uninstall %s" package-name)))
 
 (defun android-start-activity (package class)
  "Start the activity PACKAGE/CLASS in the Android emulator. This expects the SDK tools directory to be in the current path."