audio/suil: fix dependency (and packaging)

libsuil_x11_in_qt5.so was not built as it now depends on qt5 x11extras
(the condition for x11-in_qt5 changed from "HAVE_QT5" to "HAVE_QT5 and
HAVE_QT5_X11" in wscript, and the configure stage reported
'Qt5X11Extras >= 5.1.0' as missing).

Approved by: just-fix-it