Pull up following revision(s) (requested by riastradh in ticket #1828):

sys/stand/efiboot/efiboot.c: revision 1.23

efiboot: Duplicate efi_bootdp before we clobber it in efi_net_probe.

Patch from jakllsch@.  Makes Socionext Synquacer boot considerably
more reliably.

PR kern/58075

(martin)