auto-t: add copy_to_hotspot

Initially the solution to copying files to .hotspot was to use the
existing copy_to_storage, but allow full directory copying. Doing it
this way does not allow us to copy single files into .hotspot which
makes it difficult to test single configurations in several consecutive
tests.

This adds a new API, copy_to_hotspot, where a single hotspot config
can be provided. clear_storage was also modified to clear out the
.hotspot directory in addition to the regular storage directory.

autotests/util/iwd.py

@@ -947,6 +947,7 @@ class IWD(AsyncOpAbstract):
     @staticmethod
     def clear_storage():
         os.system('rm -rf ' + IWD_STORAGE_DIR + '/*')
+        os.system('rm -rf ' + IWD_STORAGE_DIR + '/.hotspot/*')
 
     @staticmethod
     def create_in_storage(file_name, file_content):
@@ -961,10 +962,18 @@ class IWD(AsyncOpAbstract):
 
         assert not os.path.isabs(source)
 
-        if os.path.isdir(source):
-            shutil.copytree(source, IWD_STORAGE_DIR + "/%s" % source)
-        else:
-            shutil.copy(source, IWD_STORAGE_DIR)
+        shutil.copy(source, IWD_STORAGE_DIR)
+
+    @staticmethod
+    def copy_to_hotspot(source):
+        import shutil
+
+        assert not os.path.isabs(source)
+
+        if not os.path.exists(IWD_STORAGE_DIR + "/.hotspot"):
+            os.mkdir(IWD_STORAGE_DIR + "/.hotspot")
+
+        shutil.copy(source, IWD_STORAGE_DIR + "/.hotspot")
 
     @staticmethod
     def remove_from_storage(file_name):