kernel: drm/amd/display: Validate payload length and link_index in dc_process_dmub_aux_transfer_async

In the Linux kernel, the following vulnerability has been resolved: drm/amd/display: Validate payload length and linkindex in dcprocessdmubauxtransferasync Why&How dcprocessdmubauxtransferasync copies payload-length bytes into a 16-byte stack buffer dpaux.data16 guarded only by an ASSERT, which i...