pidgin/pidgin

Fix the Windows build

16 months ago, Gary Kramlich
fcc390443714
Fix the Windows build

Include pidgindisplaywindow.h in gtkwin32dep.c which was causing the build to
fail.

Testing Done:
Compiled and ran on Windows.

Reviewed at https://reviews.imfreedom.org/r/2246/
syntax: glob
.*.swp
.DS_Store
.flatpak-builder
*.pyc
*~
\#*\#
syntax: regexp
^build(.+)?\/
win32-install-dir(\.release)?
po\/pidgin\.pot$
^subprojects\/.+\/