scsi_dh_alua: uninitialized variable in alua_check_vpd()

The pg_updated variable is support to be set to false at the start but
it is uninitialized.

Fixes: cb0a168c ('scsi_dh_alua: update 'access_state' field')
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Hannes Reinicke <hare@suse.de>
Reviewed-by: Manoj Kumar <manoj@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>