[SCSI] wd33c93: fix up cut and paste error

The three drivers: a2091, gvp11 and mvme147 have erroneous references
to a3000_host.  Fix these to be references to the proper host
variable.

Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
diff --git a/drivers/scsi/a2091.c b/drivers/scsi/a2091.c
index 1d1bb25..07d572f 100644
--- a/drivers/scsi/a2091.c
+++ b/drivers/scsi/a2091.c
@@ -179,9 +179,9 @@
 	DMA(instance)->DAWR = DAWR_A2091;
 	regs.SASR = &(DMA(instance)->SASR);
 	regs.SCMD = &(DMA(instance)->SCMD);
-	HDATA(a3000_host)->no_sync = 0xff;
-	HDATA(a3000_host)->fast = 0;
-	HDATA(a3000_host)->dma_mode = CTRL_DMA;
+	HDATA(instance)->no_sync = 0xff;
+	HDATA(instance)->fast = 0;
+	HDATA(instance)->dma_mode = CTRL_DMA;
 	wd33c93_init(instance, regs, dma_setup, dma_stop, WD33C93_FS_8_10);
 	request_irq(IRQ_AMIGA_PORTS, a2091_intr, IRQF_SHARED, "A2091 SCSI",
 		    instance);