INT 6F - HP Vectra EX-BIOS - "F_STR_GET_INDEX" - GET INDEX FOR STRING
	AH = 48h
	BP = 0012h (driver ID of V_SYSTEM)
	ES:DI -> ASCIZA NUL-terminated ASCII string.	The ASCIZ string "ABC" consists of the four bytes 41h, 42h, 43h, and 00h.  Unless otherwise specified, maximum lengths given in the interrupt list do not include the terminating NUL. string
Return: AH = status (00h,other) (see #03744 at AH=00h"HP Vectra")
	BP,DS destroyed
	---if successful---
	BX = index for the given string
SeeAlso: AH=00h"HP Vectra",AH=40h/BP=0012h,AH=46h/BP=0012h