INT 21 P - Phar Lap 386/DOS-Extender - GET REAL-MODE INTERRUPT VECTOR           
	AX = 2503h
	CL = interrupt number
Return: CF clear
	EBX = CS:IP(Internet Protocol) The lower level (transport layer) of the TCP/IP protocol suite.	See also TCP, TCP/IP. of real-mode interrupt handler
Note:	this function is also supported by FlashTek X-32VM
SeeAlso: AX=2502h,AX=2504h,AH=35h,INT 31/AX=0200h