wireshark-dissector: Fix Windows build about libtw2 HOT 2 CLOSED

From Discord:

[3:30 PM]saibotu: it fails to import wmem_alloc because it was moved from libwireshark to libwsutil in 3.6
[3:32 PM]heinrich5991: oh, thanks!
[3:32 PM]heinrich5991: how did you find that out?
[3:36 PM]saibotu: just ran wireshark in x64dbg with exception breakpoints
[3:38 PM]heinrich5991: thanks 🙂 the "just" is something I wouldn't even have thought of
[3:41 PM]heinrich5991: this was already a great help. if you have some more time, what is an exception breakpoint? does it refer to C++ exceptions? or SEH? and you saw the error message/symbol name in the breakpoint?
[4:31 PM]saibotu: Not really that familiar with exception handling on windows, but I think this is SEH. When this is set to break on first chance, it breaks before the exception is passed to the application.

[4:31 PM]saibotu: When it breaks you get First chance exception on 00007FFF7832FCAD (C0000139, STATUS_ENTRYPOINT_NOT_FOUND)! and r12 points to wmem_alloc
[4:32 PM]heinrich5991: to the string wmem_alloc?
[4:32 PM]saibotu: yeah
[4:32 PM]heinrich5991: nice, thanks for the explanation 🙂 I might be able to reproduce it next time

from libtw2.

Thanks to @fokkonaut for testing. :)

from libtw2.