pidgin/pidgin

Add missing self-referential #include.

2020-11-20, Elliott Sales de Andrade
406ff566ad57
Add missing self-referential #include.

Fixes a function-without-prototype warning.

Testing Done:
Compile.

Reviewed at https://reviews.imfreedom.org/r/245/
syntax: glob
.*.swp
.DS_Store
.flatpak-builder
*.pyc
*~
\#*\#
subprojects/*/
syntax: regexp
^build(.+)?\/
win32-install-dir(\.release)?