mm: fix <linux/pagemap.h> stray kernel-doc notation

mm: fix <linux/pagemap.h> stray kernel-doc notation

Delete stray (second) function description in find_lock_page()
kernel-doc notation.

Note: scripts/kernel-doc just ignores the second function description.

Fixes: 2457aec63745e ("mm: non-atomically mark page accessed during page cache allocation where possible")
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Randy Dunlap <[email protected]>
Reported-by: Matthew Wilcox <[email protected]>
Cc: Mel Gorman <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>