Attempt to locate the qmlcachegen binary in the host bin directory if
possible.
Task-number: QTBUG-68724
Change-Id: If0d28408a316b3dd33f4734464e0d5fe44c9fc2c
Reviewed-by: Rolf Eike Beer <eb@emlix.com>
Reviewed-by: Simon Hausmann <simon.hausmann@qt.io>