cbdma: skip initializing any PCI devices

In lieu of using the Linux IOAT driver, we don't want to muck with the
same PCI device another driver is using.

Signed-off-by: Barret Rhoden <brho@cs.berkeley.edu>
diff --git a/kern/drivers/dev/cbdma.c b/kern/drivers/dev/cbdma.c
index 9ec2ce0..e68ae45 100644
--- a/kern/drivers/dev/cbdma.c
+++ b/kern/drivers/dev/cbdma.c
@@ -855,6 +855,9 @@
 	int id;
 	struct pci_device *pci_iter;
 
+	printk("cbdma: skipping it\n");
+	return;
+
 	/* assigning global variables */
 	pci             = NULL;
 	mmio            = NULL;