staging/rdma/hfi1: Don't attempt to qualify or tune loopback plugs

Loopback plugs used for testing hardware don't need to be qualified to
bring the link up unlike production cables. This patch adds an exception
for loopback plugs to the QSFP and SerDes tuning algortihm.
Reviewed-by: NDean Luick <dean.luick@intel.com>
Signed-off-by: NEaswar Hariharan <easwar.hariharan@intel.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

drivers/staging/rdma/hfi1/platform.c

@@ -737,7 +737,8 @@ void tune_serdes(struct hfi1_pportdata *ppd)
 	ppd->driver_link_ready = 0;
 	ppd->offline_disabled_reason = HFI1_ODR_MASK(OPA_LINKDOWN_REASON_NONE);
 
-	if (loopback == LOOPBACK_SERDES || loopback == LOOPBACK_LCB ||
+	/* Skip the tuning for testing (loopback != none) and simulations */
+	if (loopback != LOOPBACK_NONE ||
 	    ppd->dd->icode == ICODE_FUNCTIONAL_SIMULATOR ||
 	    !dd->pcfg_cache.cache_valid) {
 		ppd->driver_link_ready = 1;