Simplify construction of injected bundle path by defining PKGLIBDIR for GTK, as is already done for WPE.
Pull request: https://github.com/WebKit/WebKit/pull/9405
Committed 259679@main (19363b5213a1): <https://commits.webkit.org/259679@main> Reviewed commits have been landed. Closing PR #9405 and removing active labels.