IB/mthca, mlx4_core: Fix typo in comment

s/signifant/significant/

Signed-off-by: Roland Dreier <rolandd@cisco.com>
diff --git a/drivers/net/mlx4/fw.c b/drivers/net/mlx4/fw.c
index cfa5cc0..ab259b2 100644
--- a/drivers/net/mlx4/fw.c
+++ b/drivers/net/mlx4/fw.c
@@ -477,7 +477,7 @@
 
 	MLX4_GET(fw_ver, outbox, QUERY_FW_VER_OFFSET);
 	/*
-	 * FW subminor version is at more signifant bits than minor
+	 * FW subminor version is at more significant bits than minor
 	 * version, so swap here.
 	 */
 	dev->caps.fw_ver = (fw_ver & 0xffff00000000ull) |