m68k/mac: fix powerbook 150 adb_type

The PowerBook 150 is a actually a Duo underneath. Fix the adb_type.

Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
diff --git a/arch/m68k/mac/config.c b/arch/m68k/mac/config.c
index 101a8b7..b20b131 100644
--- a/arch/m68k/mac/config.c
+++ b/arch/m68k/mac/config.c
@@ -674,7 +674,7 @@
 	}, {
 		.ident		= MAC_MODEL_PB150,
 		.name		= "PowerBook 150",
-		.adb_type	= MAC_ADB_PB1,
+		.adb_type	= MAC_ADB_PB2,
 		.via_type	= MAC_VIA_IIci,
 		.scsi_type	= MAC_SCSI_OLD,
 		.ide_type	= MAC_IDE_PB,