System Sprite Pool
------------------

The system sprite pool is no longer controlled by the kernel.
This area is now under the control of the SpriteUtils module.
With this change, a legacy system call has been removed. This should not
affect modern software.

OS_Byte 163, 242, 65
=> R0 = 163
   R1 = 242
   R2 = 65
<= R1 = packed information (see PRM 1-655)
   R2 = 0

This SWI no longer returns the size of the system sprite area. Applications
should use OS_ReadDynamicArea to obtain this information.

The system sprite area should not be used by modern applications, and this
change should not affect any recent software.
