Add a module_path_check for vendor files

When this is enabled we ensure that files from the vendor directory
get installed to /system/vendor/* instead of elsewhere in /system/*.

This changes the PRODUCT_RESTRICT_VENDOR_FILES variable
to accept "owner", "path", "owner path", or "all".
"true" will still only enforce vendor file owner restrictions.

Change-Id: I4598130a590ad56976e011f4cb2a9f5f227d5732