m68k/mac: Skip VIA port setup unless RTC is connected

Those Mac models which don't connect their RTC to VIA1 port B probably
have something else connected to those pins. Just leave them the way we
found them. Make the port B setup conditional on via_type, to match the
RTC accessors in arch/m68k/mac/misc.c.
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>

arch/m68k/mac/via.c

@@ -197,13 +197,18 @@ void __init via_init(void)
 		via1[vBufB] |= 0x40;
 	}
 
-	/*
-	 * Set the RTC bits to a known state: all lines to outputs and
-	 * RTC disabled (yes that's 0 to enable and 1 to disable).
-	 */
-
-	via1[vDirB] |= (VIA1B_vRTCEnb | VIA1B_vRTCClk | VIA1B_vRTCData);
-	via1[vBufB] |= (VIA1B_vRTCEnb | VIA1B_vRTCClk);
+	switch (macintosh_config->adb_type) {
+	case MAC_ADB_IOP:
+	case MAC_ADB_II:
+	case MAC_ADB_PB1:
+		/*
+		 * Set the RTC bits to a known state: all lines to outputs and
+		 * RTC disabled (yes that's 0 to enable and 1 to disable).
+		 */
+		via1[vDirB] |= VIA1B_vRTCEnb | VIA1B_vRTCClk | VIA1B_vRTCData;
+		via1[vBufB] |= VIA1B_vRTCEnb | VIA1B_vRTCClk;
+		break;
+	}
 
 	/* Everything below this point is VIA2/RBV only... */