[omxplayer] When setting fullscreen flag we don't want noaspect

We set the fullscreen on 3d videos to avoid scaling breaking the 3d affect.
However we also set the noaspect flag which means widescreen videos (e.g. 1920x800) will get stretched vertically which is unwanted.
Merge pull request #4404 from popcornmix/3daspect

[omxplayer] When setting fullscreen flag we don't want noaspect