bna: scope and dead code cleanup

As suggested by Stephen Hemminger:
1) Made functions and data structures static wherever possible.
2) Removed unused code.

Signed-off-by: Debashis Dutt <ddutt@brocade.com>
Signed-off-by: Rasesh Mody <rmody@brocade.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/bna/cna_fwimg.c b/drivers/net/bna/cna_fwimg.c
index 0bd1d37..e8f4ecd 100644
--- a/drivers/net/bna/cna_fwimg.c
+++ b/drivers/net/bna/cna_fwimg.c
@@ -22,7 +22,7 @@
 static u32 *bfi_image_ct_cna;
 static u32 bfi_image_ct_cna_size;
 
-u32 *
+static u32 *
 cna_read_firmware(struct pci_dev *pdev, u32 **bfi_image,
 			u32 *bfi_image_size, char *fw_name)
 {