Fix typo in LLaVa documentation (#38618)
* Fix typo in LLaVa documentation
In exactly one section, LlavaImageProcessor was spelt wrongly as LLavaImageProcessor, which throws off copy-pasting the section.
* Fix LlavaImageProcessor url to make it valid (and copypaste-able)
Earlier, the URL contained the entire HF prefix. This commit removes that to ensure that the code block can be copied and run as is.
