qt security update

1:4.8.7-8 - Fix QImage allocation failure in qgifhandler Resolves: bz1667863 - Fix QTgaFile CPU exhaustion Resolves: bz1667879 - Fix QBmpHandler segmentation fault on malformed BMP file Resolves: bz1667862 1:4.8.7-7 - Fix crash when parsing malformed url reference in svg Resolves: bz1667882...