pidgin/pidgin

Fix a missing include for at least windows in glibcompat.h
release-2.x.y
2021-02-12, Gary Kramlich
6f5dea8b78f7
Fix a missing include for at least windows in glibcompat.h

Testing Done:
Local compile only.

Reviewed at https://reviews.imfreedom.org/r/500/
installed_m4=purple.m4
EXTRA_DIST=$(installed_m4)
m4datadir=$(datadir)/aclocal
m4data_DATA=$(installed_m4)