b43: allocate receive buffers big enough for max frame len + offset

Otherwise, skb_put inside of dma_rx can fail...

	https://bugzilla.kernel.org/show_bug.cgi?id=32042

Signed-off-by: John W. Linville <linville@tuxdriver.com>
Acked-by: Larry Finger <Larry.Finger@lwfinger.net>
Cc: stable@kernel.org
diff --git a/drivers/net/wireless/b43/dma.c b/drivers/net/wireless/b43/dma.c
index 3d5566e..ff0f5ba 100644
--- a/drivers/net/wireless/b43/dma.c
+++ b/drivers/net/wireless/b43/dma.c
@@ -1536,7 +1536,7 @@
 		dmaaddr = meta->dmaaddr;
 		goto drop_recycle_buffer;
 	}
-	if (unlikely(len > ring->rx_buffersize)) {
+	if (unlikely(len + ring->frameoffset > ring->rx_buffersize)) {
 		/* The data did not fit into one descriptor buffer
 		 * and is split over multiple buffers.
 		 * This should never happen, as we try to allocate buffers