fs/libfs.c: fix kernel-doc warning

Fix kernel-doc warning in fs/libfs.c:

  fs/libfs.c:496: warning: Excess function parameter 'available' description in 'simple_write_end'

Link: http://lkml.kernel.org/r/5fc9d70b-e377-0ec9-066a-970d49579041@infradead.org
Fixes: ad2a722f ("libfs: Open code simple_commit_write into only user")
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Boaz Harrosh <boazh@netapp.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

fs/libfs.c

@@ -473,8 +473,7 @@ EXPORT_SYMBOL(simple_write_begin);
 
 /**
  * simple_write_end - .write_end helper for non-block-device FSes
- * @available: See .write_end of address_space_operations
- * @file: 		"
+ * @file: See .write_end of address_space_operations
  * @mapping: 		"
  * @pos: 		"
  * @len: 		"