fs: remove excess kernel-doc

Delete excess kernel-doc notation in fs/ subdirectory:

Warning(linux-2.6.27-git10//fs/jbd/transaction.c:886): Excess function parameter or struct member 'credits' description in 'journal_get_undo_access'

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>