block: fix current kernel-doc warnings

Fix block kernel-doc warnings:

Warning(linux-2.6.27-git4//fs/block_dev.c:1272): No description found for parameter 'path'
Warning(linux-2.6.27-git4//block/blk-core.c:1021): No description found for parameter 'cpu'
Warning(linux-2.6.27-git4//block/blk-core.c:1021): No description found for parameter 'part'
Warning(/var/linsrc/linux-2.6.27-git4//block/genhd.c:544): No description found for parameter 'partno'

Signed-off-by: Randy Dunlap <[e-mail]>
Signed-off-by: Jens Axboe <[e-mail]>

block/blk-core.c

···
 }
 
 /**
- * part_round_stats()	- Round off the performance stats on a struct
- * disk_stats.
+ * part_round_stats() - Round off the performance stats on a struct disk_stats.
+ * @cpu: cpu number for stats access
+ * @part: target partition
  *
  * The average IO queue length and utilisation statistics are maintained
  * by observing the current state of the queue length and the amount of

block/genhd.c

···
 /**
  * get_gendisk - get partitioning information for a given device
  * @devt: device to get partitioning information for
- * @part: returned partition index
+ * @partno: returned partition index
  *
  * This function gets the structure containing partitioning
  * information for the given device @devt.

fs/block_dev.c

···
 
 /**
  * lookup_bdev  - lookup a struct block_device by name
- * @pathname:	special file representing the block device
+ * @path:	special file representing the block device
  *
  * Get a reference to the blockdevice at @pathname in the current
  * namespace if possible and return it.  Return ERR_PTR(error)