include QtX11Extras/QX11Info and require Qt5X11Extras

Created by: Idesmi

On openSUSE Tumbleweed, cmake isn't able to find QX11Info if QtX11Extras is not specified. Needs similar action in submodule qhotkey.

I can confirm that with the patch applied the package builds and works properly: https://build.opensuse.org/package/show/home:iDesmI:kf5/crow-translate

Please doublecheck this commit.