cxl: Add missing return to cdat read error path

Add a return to the error path when cxl_cdat_read_table() fails. Current
code continues with the table pointer points to freed memory.

Fixes: 7a877c92 ("cxl/pci: Simplify CDAT retrieval error path")
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Reviewed-by: Davidlohr Bueso <dave@stgolabs.net>
Link: https://lore.kernel.org/r/168382793506.3510737.4792518576623749076.stgit@djiang5-mobl3


Signed-off-by: Dan Williams <dan.j.williams@intel.com>