updated ENC624j6net driver

- fixes to gcc native and cross compilation settings
  - implemented hardware based multicast filtering hashes, resulting
    in less unwanted traffic to our Amigas (especially Bonjour, UPNP and such)
  - MULTICAST option in envarc:sana2/enc624j6net.config will now
    allow all multicast traffic as opposed to the default fine grained
    filtering behaviour

Driver/baxnet/source/kprintf.asm

@@ -14,11 +14,18 @@ _LVORawIOInit			equ	-$1f8
 _LVORawMayGetChar		equ 	-$1fe
 	endc
 
-	XDEF	_KPrintF
+;	XDEF	_KPrintF
+	XDEF	_KPrintFa0a1
+
+;_KPrintF:
+	rts
+	move.l	4(sp),a0
+	lea	8(sp),a1
+	; fall through
 
 ;A0 = format
 ;A1 = arguments
-_KPrintF:
+_KPrintFa0a1:
 ;	ifd	DEBUG
 
 	movem.l	d0-d2/a0-a3/a6,-(sp)