INT 14 - MX5 Extended FOSSIL(Fido/Opus/Seadog Standard Interface Layer)  A standardized API for performing serial I/O, originally used by the Fido and Opus bulletin- board software and Seadog bulletin-board mailer, but now in wider use. - UNINSTALL
	AX = E005h
Return: BX = segment of MX5's memory block or 0000h on failure
Note:	caller must free the returned memory block to complete the uninstall
SeeAlso: AX=E006h