[BNX2]: Add indirect spinlock.

The indirect register access method will be used by more than one
caller in BH context (NAPI poll and timer), so a spinlock is required.

Signed-off-by: Michael Chan <mchan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/bnx2.h b/drivers/net/bnx2.h
index 124bd03..ba175a8 100644
--- a/drivers/net/bnx2.h
+++ b/drivers/net/bnx2.h
@@ -6522,6 +6522,7 @@
 
 	/* Used to synchronize phy accesses. */
 	spinlock_t		phy_lock;
+	spinlock_t		indirect_lock;
 
 	u32			phy_flags;
 #define PHY_SERDES_FLAG			1