INT 6F - HP Vectra EX-BIOS - "F_RAM_RET" - RESERVE EX-BIOS MEMORY

	AH = 20h
	BP = 0012h (driver ID for V_SYSTEM)
	BX = new value for "last-used DS"
	DX = new value for "maximum DS"
Return: AH = status (00h) (see #03744 at INT 6F/AH=00h"HP Vectra")
	BP,DS destroyed
Note:	the F_INS_FIXGETDS and F_INS_FREEGETDS functions
	  (see AH=0Eh/BP=0012h,AH=14h/BP=0012h) also modify the values returned
	  by this call, requiring care if both methods are used to allocate
	  memory
SeeAlso: AH=00h"HP Vectra",AH=0Eh/BP=0012h,AH=14h/BP=0012h,AH=1Eh/BP=0012h