NTB: Alter link-state API to support multi-port devices

Multi-port devices permit the NTB connections between multiple domains,
so a local device can have NTB link being up with one peer and being
down with another. NTB link-state API is appropriately altered to return
a bitfield of the link-states between the local device and possible peers.

Signed-off-by: Serge Semin <fancer.lancer@gmail.com>
Acked-by: Allen Hubbe <Allen.Hubbe@dell.com>
Signed-off-by: Jon Mason <jdmason@kudzu.us>
diff --git a/drivers/ntb/hw/intel/ntb_hw_intel.c b/drivers/ntb/hw/intel/ntb_hw_intel.c
index 7b3b6fd..6b25bf8 100644
--- a/drivers/ntb/hw/intel/ntb_hw_intel.c
+++ b/drivers/ntb/hw/intel/ntb_hw_intel.c
@@ -1171,7 +1171,7 @@ static int intel_ntb_mw_set_trans(struct ntb_dev *ntb, int idx,
 	return 0;
 }
 
-static int intel_ntb_link_is_up(struct ntb_dev *ntb,
+static u64 intel_ntb_link_is_up(struct ntb_dev *ntb,
 				enum ntb_speed *speed,
 				enum ntb_width *width)
 {