accel/qaic: Treat remaining == 0 as error in find_and_map_user_pages()

In the Linux kernel, the following vulnerability has been resolved: accel/qaic: Treat remaining == 0 as error in find_and_map_user_pages() Currently, if find_and_map_user_pages() takes a DMA xfer request from the user with a length field set to 0, or in a rare case, the host receives QAIC_TRANS_DMA_XFER_CONT from the device where resources->xferred_dma_size is equal to the requested transaction size, the function will return 0 before allocating an sgt or setting the fields of the dma_xfer struct. In that case, encode_addr_size_pairs() will try to access the sgt which will lead to a general protection fault. Return an EINVAL in case the user provides a zero-sized ALP, or the device requests continuation after all of the bytes have been transferred.