The tslib plugin must be built by hand.
It's not enabled by default and cannot be configured to be built
with the rest of the plugins, from a top-level make execution.
As this is really annoying, embedded frameworks such as open-embedded  or
buildroot will have to resort to patching Qt in order to support this option.
Looks like Qt5 should have some --enable-tslib or --with-tslib option in its