[SCSI] qla2xxx: Add Fibre Channel Event (FCE) tracing support.

[SCSI] qla2xxx: Add Fibre Channel Event (FCE) tracing support.

FCE support enables the firmware to record FC extended link
services and basic link services frames which have been
transmitted and received by the ISP.  This allows for a limited
view of the FC traffic through the ISP without using a FC
analyzer.  This can be useful in situations where a physical
connection to the FC bus is not possible.

The driver exports this information in two ways -- first, via a
debugfs node exported for all supported ISPs under:

	<debugfs_mount_point>/qla2xxx/qla2xxx_<host_no>/fce

where a read of the 'fce' file will provide a snapshot of the
firmware's FCE buffer; and finally, the FCE buffer will be
extracted during a firmware-dump scenario.

Signed-off-by: Andrew Vasquez <andrew.vasquez@qlogic.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>