CVE-2025-37860

In the Linux kernel, the following vulnerability has been resolved:

sfc: fix NULL dereferences in ef100_process_design_param()

Since cited commit, ef100_probe_main() and hence also
ef100_check_design_params() run before efx->net_dev is created;
consequently, we cannot netif_set_tso_max_size() or _segs() at this
point.
Move those netif calls to ef100_probe_netdev(), and also replace
netif_err within the design params code with pci_err.