igb: Bump version number

With recent changes, need to bump the driver version to reflect the
changes.
Signed-off-by: Todd Fujinaka <todd.fujinaka@intel.com>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

drivers/net/ethernet/intel/igb/igb_main.c

@@ -39,7 +39,7 @@
 #include "igb.h"
 
 #define MAJ 5
-#define MIN 4
+#define MIN 6
 #define BUILD 0
 #define DRV_VERSION __stringify(MAJ) "." __stringify(MIN) "." \
 __stringify(BUILD) "-k"