INT 2F - Novell NetWare - SHELL 3.01d BROADCAST - SET SHELL INT 21 HANDLER
        AX = 7A81h
        CX:DX -> shell's INT 21h entry point
Return: nothing
Notes:  the shell calls this function as it loads to allow interested TSRs
          and drivers to make a local copy of the shell's entry point
        must be passed through so that all interested programs see it