INT 31H 0503H: Resize Memory Block

                                                    Compatibility: DPMI 0.9+ 
 Expects: AX    0503H
          BX:CX new size of block, in bytes (must not be 0)
          SI:DI handle of memory block to resize
 Returns: CF    NC (clear) if successful; else AX = DPMI Error Code
          BX:CX new linear address of allocated block
          SI:DI new handle used to resize and free this block
    Info: Resizes a block of memory that was previously allocated via
          INT 31H 0501H or INT 31H 0504H.

          It is the client's responsibility to update descriptors that map
          this memory.  See, for instance, INT 31H 0007H (set segment base
          address) and INT 31H 0008H (set segment limit).

See Also: DPMI API
          INT 2fH: Multiplex Interrupt
          DOS Functions