Fix QT_HOST_LIBS qmake patching

This amends commit 5e1f41cd070130d34090be506cc3e239d3159e8b

Task-number: QTIFW-262
Change-Id: Iaa941bd6d30c5e5387505ca7674dda256afc66da
Reviewed-by: Iikka Eklund <iikka.eklund@digia.com>
Reviewed-by: Tim Jenssen <tim.jenssen@digia.com>