i40e: Error handling for link event

There exists an intermittent bug which causes the 'Link Detected'
field reported by the 'ethtool <iface>' command to be 'Yes' when
in fact, there is no link. This patch fixes the problem by
enabling temporary link polling when i40e_get_link_status returns
an error. This causes the driver to remember that an admin queue
command failed and polls, until the function returns with a success.

Change-Id: I64c69b008db4017b8729f3fc27b8f65c8fe2eaa0
Signed-off-by: Harshitha Ramamurthy <harshitha.ramamurthy@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 f4c4ee3..82d8040 100644
--- a/drivers/net/ethernet/intel/i40e/i40e.h
+++ b/drivers/net/ethernet/intel/i40e/i40e.h
@@ -349,6 +349,7 @@ struct i40e_pf {
 #define I40E_FLAG_HAVE_CRT_RETIMER		BIT_ULL(52)
 #define I40E_FLAG_PTP_L4_CAPABLE		BIT_ULL(53)
 #define I40E_FLAG_WOL_MC_MAGIC_PKT_WAKE		BIT_ULL(54)
+#define I40E_FLAG_TEMP_LINK_POLLING		BIT_ULL(55)
 
 	/* tracks features that get auto disabled by errors */
 	u64 auto_disable_flags;