IB/ipath: Prevent link-recovery code from negating admin disable

The link can be put in LINKDOWN_DISABLE state either locally or via a
MAD.  However, the link-recovery code will take it out of that state as
a side-effect of attempts to clear SerDes/XGXS issues.

We add a flag to indicate "link is down on purpose, leave it alone."

Signed-off-by: Michael Albaugh <michael.albaugh@qlogic.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>

drivers/infiniband/hw/ipath/ipath_intr.c

@@ -309,6 +309,8 @@ static void handle_e_ibstatuschanged(struct ipath_devdata *dd,
 		lastlstate == INFINIPATH_IBCS_L_STATE_DOWN) {
 		/* transitioned to UP */
 		if (dd->ipath_f_ib_updown(dd, 1, ibcs)) {
+			/* link came up, so we must no longer be disabled */
+			dd->ipath_flags &= ~IPATH_IB_LINK_DISABLED;
 			ipath_cdbg(LINKVERB, "LinkUp handled, skipped\n");
 			goto skip_ibchange; /* chip-code handled */
 		}