NTB: switchtec: Export class symbol for use in upper layer driver

We export the class pointer symbol and add an extern define in the
Switchtec header file.
Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Reviewed-by: Stephen Bates <sbates@raithlin.com>
Reviewed-by: Kurt Schwemmer <kurt.schwemmer@microsemi.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Jon Mason <jdmason@kudzu.us>

drivers/pci/switch/switchtec.c

@@ -33,9 +33,11 @@ module_param(max_devices, int, 0644);
 MODULE_PARM_DESC(max_devices, "max number of switchtec device instances");
 
 static dev_t switchtec_devt;
-static struct class *switchtec_class;
 static DEFINE_IDA(switchtec_minor_ida);
 
+struct class *switchtec_class;
+EXPORT_SYMBOL_GPL(switchtec_class);
+
 enum mrpc_state {
 	MRPC_IDLE = 0,
 	MRPC_QUEUED,

include/linux/switchtec.h

@@ -276,4 +276,6 @@ static inline struct switchtec_dev *to_stdev(struct device *dev)
 	return container_of(dev, struct switchtec_dev, dev);
 }
 
+extern struct class *switchtec_class;
+
 #endif