build_wrapper: Do not upload submodules_{tar,zip}

We don't even release those two directories, so there is no need
to save them anywhere.

It is enough to just copy the content to /submodules/ which is the
actual directory that we publish for the release.

Change-Id: I57c44f35394df045486c158520ad0e986302ffd0
Reviewed-by: Matti Paaso <matti.paaso@digia.com>
Reviewed-by: Iikka Eklund <iikka.eklund@digia.com>
build_wrapper: Remove qtjsbackend from the ignore list

qtjsbacked does not even exist for Qt 5.2.x, so there is no need
to ignore it.

Change-Id: Ica9b3cb588f8f3de91b8b7f6c13b1417dd504fab
Reviewed-by: Matti Paaso <matti.paaso@digia.com>
Reviewed-by: Iikka Eklund <iikka.eklund@digia.com>
build_wrapper: Remove qtwinextras from the ignore list

qtwinextras will be part of the Qt 5.2.0 alpha release (at least)

Change-Id: I1b153f7917219cc650e1bc3c78e01b0d151a3458
Reviewed-by: Matti Paaso <matti.paaso@digia.com>
Reviewed-by: Iikka Eklund <iikka.eklund@digia.com>