Npcap 1.73 and earlier: miscalculated timestamps when multiple modes are in use

[dmiller-nmap]

When multiple capture handles are open and at least 2 use different timestamp modes, each captured packet will have the same timestamp value regardless of which handle receives it and which timestamp mode is requested. The value (and hence the effective timestamp mode) will be chosen based on the oldest capture handle that processes the packet. This can lead to unexpected time drift or backwards time jumps relative to the expected values under a different timestamp mode.