Use ECMGeneratePkgConfigFile to create the pkgconfig file.

Authored by krop on Dec 21 2018, 9:16 AM.

Description

Use ECMGeneratePkgConfigFile to create the pkgconfig file.

Summary:
This also fixes the version in the .pc file.

BUG 390225
FIXED-IN: 5.55

Reviewers: cfeck, Build System, alexeymin

Reviewed By: alexeymin

Subscribers: alexeymin, kde-frameworks-devel

Tags: Frameworks

Differential Revision: https://phabricator.kde.org/D17718