Export ID_WWN_VENDOR_EXTENSION and ID_WWN_WITH_EXTENSION

Export ID_WWN_VENDOR_EXTENSION and ID_WWN_WITH_EXTENSION

Some SCSI devices use the same WWN and have a WWN extension that we
need to take into account when creating the /dev/disk/by-id/wwn
symlinks. Thus, introduce ID_WWN_WITH_EXTENSION. This property will
contain either the WWN (if no extension is present) or the WWN with
the vendor extension appended.

Example:

 # /lib/udev/ata_id/ata_id --export /dev/sda |grep WWN
 ID_WWN=0x5001517387d61905
 ID_WWN_WITH_EXTENSION=0x5001517387d61905

 # /lib/udev/scsi_id --whitelisted --export -d /dev/sdb |grep WWN
 ID_WWN=0x600508b400105df7
 ID_WWN_VENDOR_EXTENSION=0x0000e00000d80000
 ID_WWN_WITH_EXTENSION=0x600508b400105df70000e00000d80000

 # /lib/udev/scsi_id --whitelisted --export -d /dev/sdc |grep WWN
 ID_WWN=0x600508b400105df7
 ID_WWN_VENDOR_EXTENSION=0x0000e00000db0000
 ID_WWN_WITH_EXTENSION=0x600508b400105df70000e00000db0000

Signed-off-by: David Zeuthen <davidz@redhat.com>