bugfix: controlnet works in API - image no longer a dictionary

[IgorAherne]

Generating from browser works with controlnet. Generating via API didn't. Because from_dict() was making 'image' and 'mask_image' a dictionary.

In 'controlnet.py' the function 'get_input_data' this would cause exception, because unit.image was of incorrect type:

elif (unit_image < 5).all() and (unit_image_fg > 5).any():

Now, they are never a dictionary and check is fine. Both browser and api work with controlnet