scsi: aha1542: avoid uninitialized variable warnings

Gcc incorrectly detects that two variables in aha1542_queuecommand might
be used without an initialization:

scsi/aha1542.c: In function 'aha1542_queuecommand':
scsi/aha1542.c:382:16: error: 'cptr' may be used uninitialized in this function [-Werror=maybe-uninitialized]
scsi/aha1542.c:379:11: error: 'sg_count' may be used uninitialized in this function [-Werror=maybe-uninitialized]

The only user of these is doing the same check that the assigment has,
so it is actually guaranteed to work. Adding an "else" clause with a
fake initialization shuts up the warning.

Signed-off-by: Arnd Bergmann <[e-mail]>
Signed-off-by: Martin K. Petersen <[e-mail]>

drivers/scsi/aha1542.c

···
 		cptr = kmalloc(sizeof(*cptr) * sg_count, GFP_KERNEL | GFP_DMA);
 		if (!cptr)
 			return SCSI_MLQUEUE_HOST_BUSY;
+	} else {
+		sg_count = 0;
+		cptr = NULL;
 	}
 
 	/* Use the outgoing mailboxes in a round-robin fashion, because this