e1000: bump version to 7.1.9-k4

Bump the version to 7.1.9-k4 to indicate three extra changes.
Signed-off-by: Auke Kok <auke-jan.h.kok@intel.com>

drivers/net/e1000/e1000_main.c

@@ -36,7 +36,7 @@ static char e1000_driver_string[] = "Intel(R) PRO/1000 Network Driver";
 #else
 #define DRIVERNAPI "-NAPI"
 #endif
-#define DRV_VERSION "7.1.9-k2"DRIVERNAPI
+#define DRV_VERSION "7.1.9-k4"DRIVERNAPI
 char e1000_driver_version[] = DRV_VERSION;
 static char e1000_copyright[] = "Copyright (c) 1999-2006 Intel Corporation.";