IB/core: Add get FW version string to the core

Allow for a common core function to get firmware version strings
from the individual devices.

In later patches this format can then then be used to pass a
properly formated version string through the IPoIB layer.

The problem with the current code in the IPoIB layer is that it is
specific to certain hardware types.

Furthermore, this gives us a common function through which the core
can provide a common sysfs entry.  Eventually we may want to
remove the sysfs export but this provides for user space backwards
compatibility.

Reviewed-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Ira Weiny <ira.weiny@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
diff --git a/drivers/infiniband/core/device.c b/drivers/infiniband/core/device.c
index 5c155fa..760ef60 100644
--- a/drivers/infiniband/core/device.c
+++ b/drivers/infiniband/core/device.c
@@ -311,6 +311,15 @@
 	return 0;
 }
 
+void ib_get_device_fw_str(struct ib_device *dev, char *str, size_t str_len)
+{
+	if (dev->get_dev_fw_str)
+		dev->get_dev_fw_str(dev, str, str_len);
+	else
+		str[0] = '\0';
+}
+EXPORT_SYMBOL(ib_get_device_fw_str);
+
 /**
  * ib_register_device - Register an IB device with IB core
  * @device:Device to register