mm/swap.c: make functions and their kernel-doc agree

Fix some basic kernel-doc notation in mm/swap.c:

 - for function lru_cache_add_anon(), make its kernel-doc function name
   match its function name and change colon to hyphen following the
   function name

 - for function pagevec_lookup_entries(), change the function parameter
   name from nr_pages to nr_entries since that is more descriptive of
   what the parameter actually is and then it matches the kernel-doc
   comments also

Fix function kernel-doc to match the change in commit 67fd707f:

 - drop the kernel-doc notation for @nr_pages from
   pagevec_lookup_range() and correct the function description for that
   change

Link: http://lkml.kernel.org/r/3b42ee3e-04a9-a6ca-6be4-f00752a114fe@infradead.org
Fixes: 67fd707f

 ("mm: remove nr_pages argument from pagevec_lookup_{,range}_tag()")
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Jan Kara <jack@suse.cz>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Hugh Dickins <hughd@google.com>
Cc: Michal Hocko <mhocko@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>