QtIFW

Don't re-use QProcess in different tries

Don't assume you can recycle the QProcess object when trying again.
Instead create a new one every time ... This is also what
QtPatch::qmakeValues does, and prevents spurious

  Warning: QProcess::start: Process is already running

errors.

Change-Id: Iae4904d24998c8ebeb460457b96d5adaaea99bf0
Reviewed-by: Tim Jenssen <tim.jenssen@digia.com>