qt: install QML imports on target

When selecting the Qt declarative module, all the QML imports was
built and installed to staging, but never installed to the target.

Signed-off-by: Daniel Nyström <daniel.nystrom@timeterminal.se>
Acked-by: Alexander Lukichev <alexander.lukichev@gmail.com>
Acked-by: Arnout Vandecappelle (Essensium/Mind) <arnout@mind.be>
Tested-by: Arnout Vandecappelle (Essensium/Mind) <arnout@mind.be>
Signed-off-by: Peter Korsgaard <jacmet@sunsite.dk>