Fix import for foscam (home-assistant#9140)

While waiting for a new pyfoscam release, we can fix this for users
just by changing the import. Foscam devices a pretty widely deployed,
so a regression here is definitely no fun.

Fixes Bug home-assistant#8940

homeassistant/components/camera/foscam.py

@@ -53,7 +53,7 @@ def __init__(self, device_info):
         self._name = device_info.get(CONF_NAME)
         self._motion_status = False
 
-        from foscam import FoscamCamera
+        from foscam.foscam import FoscamCamera
 
         self._foscam_session = FoscamCamera(ip_address, port, self._username,
                                             self._password, verbose=False)