[kde-frameworks/plasma] Remove unused dependencies.

Upstream commit: 3b38d57ba38ad5da923d8e99791859ad25b6f4a0

Package-Manager: portage-2.2.8-r1
[kde-frameworks/plasma] Add missing build dependency.

Is required to generate man page.

Package-Manager: portage-2.2.8-r1
[kde-frameworks/plasma] Improve OpenGL and add EGL support.

Package-Manager: portage-2.2.8-r1