swap: remove __swp_swapcount()

swap: remove __swp_swapcount()

__swp_swapcount() just encloses the calling to swap_swapcount() with
get/put_swap_device().  It is called in __read_swap_cache_async() only,
which encloses the calling with get/put_swap_device() already.  So,
__read_swap_cache_async() can call swap_swapcount() directly.

Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: "Huang, Ying" <[email protected]>
Reviewed-by: David Hildenbrand <[email protected]>
Reviewed-by: Chris Li (Google) <[email protected]>
Cc: Hugh Dickins <[email protected]>
Cc: Johannes Weiner <[email protected]>
Cc: Matthew Wilcox <[email protected]>
Cc: Michal Hocko <[email protected]>
Cc: Minchan Kim <[email protected]>
Cc: Tim Chen <[email protected]>
Cc: Yang Shi <[email protected]>
Cc: Yu Zhao <[email protected]>
Cc: Yosry Ahmed <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>