INT 2F - PCIBM PC LAN PROG REDIR.SYS internal - SET REDIRIFS ENTRY POINT
	AX = BF80h
	ES:DI -> FAR entry point to IFSsee Installable File System handler in REDIRIFS
Return: AL = FFh if installed
	    ES:DI -> internal workspace
Note:	all future IFSsee Installable File System calls to REDIR.SYS are passed to the ES:DI entry point
SeeAlso: AX=BF00h