ScummVM/ResidualVM: support hat if no stick (ex: GPI case)

By default, the gamecontrollerdb file created when starting the ScummVM/ResidualVM maps buttons, hats and sticks as defined in Recalbox. But these emulators needs the left stick to emulate the mouse.

=> when no left stick is defined for current controller, map hat as the left stick

This will allow to play ScummVM/ResidualVM games on GPI case.