Allocate the memory for a new SDLPoint and fill it with x and y

As with malloc, the new instances must the be freed with free.

Property definitions

sdl2 $ SDLPoint :: new
	# Allocate the memory for a new `SDLPoint` and fill it with `x` and `y`
	#
	# As with `malloc`, the new instances must the be freed with `free`.
	new (x, y: Int) do
		var point = new SDLPoint.malloc
		point.x = x
		point.y = y
		return point
	end
lib/sdl2/sdl2_base.nit:543,2--551,4