i40e: Protect access to VF control methods

A scenario has been found in which simultaneous
addition/removal and modification of VF's might cause
unstable behaviour, up to and including kernel panics.

Protect the methods that create/modify/destroy VF's
by locking them behind an atomically set bit in PF status
bitfield.

Signed-off-by: Jan Sokolowski <jan.sokolowski@intel.com>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
diff --git a/drivers/net/ethernet/intel/i40e/i40e.h b/drivers/net/ethernet/intel/i40e/i40e.h
index 876cac3..5595a46 100644
--- a/drivers/net/ethernet/intel/i40e/i40e.h
+++ b/drivers/net/ethernet/intel/i40e/i40e.h
@@ -146,6 +146,7 @@ enum i40e_state_t {
 	__I40E_CLIENT_SERVICE_REQUESTED,
 	__I40E_CLIENT_L2_CHANGE,
 	__I40E_CLIENT_RESET,
+	__I40E_VIRTCHNL_OP_PENDING,
 	/* This must be last as it determines the size of the BITMAP */
 	__I40E_STATE_SIZE__,
 };