xhci: Rename variables and reduce register reads.

The xhci_bus_suspend() and xhci_bus_resume() functions are a bit hard to
read, because they have an ambiguously named variable "port".  Rename it
to "port_index".  Introduce a new temporary variable, "max_ports" that
holds the maximum number of roothub ports the host controller supports.
This will reduce the number of register reads, and make it easy to change
the maximum number of ports when there are two roothubs.

Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
diff --git a/drivers/usb/host/xhci-ring.c b/drivers/usb/host/xhci-ring.c
index b36d3b0..3264d62 100644
--- a/drivers/usb/host/xhci-ring.c
+++ b/drivers/usb/host/xhci-ring.c
@@ -1163,7 +1163,7 @@
 	u32 port_id;
 	u32 temp, temp1;
 	u32 __iomem *addr;
-	int ports;
+	int max_ports;
 	int slot_id;
 
 	/* Port status change events always have a successful completion code */
@@ -1174,8 +1174,8 @@
 	port_id = GET_PORT_ID(event->generic.field[0]);
 	xhci_dbg(xhci, "Port Status Change Event for port %d\n", port_id);
 
-	ports = HCS_MAX_PORTS(xhci->hcs_params1);
-	if ((port_id <= 0) || (port_id > ports)) {
+	max_ports = HCS_MAX_PORTS(xhci->hcs_params1);
+	if ((port_id <= 0) || (port_id > max_ports)) {
 		xhci_warn(xhci, "Invalid port id %d\n", port_id);
 		goto cleanup;
 	}