Code health: Remove unused VAX transfer vector for engines

Reviewed-by: NRich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/2793)

engines/engine_vector.mar

-;
-; Transfer vector for VAX shareable image
-;
-	.TITLE ENGINE
-	.IDENT /ENGINE/
-;
-; Define macro to assist in building transfer vector entries.  Each entry
-; should take no more than 8 bytes.
-;
-	.MACRO FTRANSFER_ENTRY routine
-	.ALIGN QUAD
-	.TRANSFER routine
-	.MASK	routine
-	JMP	routine+2
-	.ENDM FTRANSFER_ENTRY
-;
-; Place entries in own program section.
-;
-	.PSECT $$ENGINE,QUAD,PIC,USR,CON,REL,LCL,SHR,EXE,RD,NOWRT
-ENGINE_xfer:
-	FTRANSFER_ENTRY bind_engine
-	FTRANSFER_ENTRY v_check
-	.BLKB 32768-<.-ENGINE_xfer>	; 64 pages total.
-	.END