core/pxe: Allow DHCP option 54 Server Identifier

Apparently some servers don't bother setting siaddr when pointing to
itself for TFTP.  Re-allow 54 but always set IPInfo.serverip from
siaddr/dhcp->sip in packet #3 (PXEReply/proxyDHCP).

Always set from siaddr if good in case parsing after-DHCP options.

Reported-by: Celelibi <celelibi@gmail.com>
Signed-off-by: Gene Cumm <gene.cumm@gmail.com>
1 file changed