Fix some more off-by-one errors in Haiku image code

Fix some more off-by-one errors in Haiku image code

* src/haiku_draw_support.cc (BView_DrawBitmapWithEraseOp):
(BView_DrawMask):
(BBitmap_transform_bitmap):
* src/haiku_support.cc (AttachCairoSurface): Adjust calculations
to take account of BRect width and height functions returning
(start - end) instead of the actual width and height of the
rectangle.