bnxt_en: Always set output parameters in bnxt_get_max_rings().

The current code returns -ENOMEM and does not bother to set the output
parameters to 0 when no rings are available.  Some callers, such as
bnxt_get_channels() will display garbage ring numbers when that happens.
Fix it by always setting the output parameters.

Fixes: 6e6c5a5 ("bnxt_en: Modify bnxt_get_max_rings() to support shared or non shared rings.")
Signed-off-by: Michael Chan <michael.chan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/broadcom/bnxt/bnxt.c

@@ -8502,11 +8502,11 @@ int bnxt_get_max_rings(struct bnxt *bp, int *max_rx, int *max_tx, bool shared)
 	int rx, tx, cp;
 
 	_bnxt_get_max_rings(bp, &rx, &tx, &cp);
+	*max_rx = rx;
+	*max_tx = tx;
 	if (!rx || !tx || !cp)
 		return -ENOMEM;
 
-	*max_rx = rx;
-	*max_tx = tx;
 	return bnxt_trim_rings(bp, max_rx, max_tx, cp, shared);
 }