memory-failure: do code refactor of soft_offline_page()

memory-failure: do code refactor of soft_offline_page()

There are too many return points randomly intermingled with some "goto
done" return points.  So adjust the function structure, one for the
success path, the other for the failure path.  Use atomic_long_inc
instead of atomic_long_add.

Signed-off-by: Xishi Qiu <[email protected]>
Signed-off-by: Jiang Liu <[email protected]>
Suggested-by: Andrew Morton <[email protected]>
Cc: Borislav Petkov <[email protected]>
Cc: Wanpeng Li <[email protected]>
Cc: Andi Kleen <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>