gplugin/gplugin

Simplify meson pkgconfig generation.
develop
2020-05-10, Elliott Sales de Andrade
7f7006358a70
Simplify meson pkgconfig generation.

This silences warnings about calling it with the wrong type of argument.
The following individuals have contributed to this project.
Ankit Vani <a@nevitus.org>
EionRobb <eion@robbmob.com>
Elliott Sales de Andrade <quantum.analyst@gmail.com>
Gary Kramlich <grim@reaperworld.com>
Jason Scherer <schereja@gmail.com>
John Bailey <rekkanoryo@rekkanoryo.org>
Mike Ruprecht <cmaiku@gmail.com>
Olaf Hering <olaf@aepfle.de>
Richard Laager <rlaager@pidgin.im>