mm, memory_failure: don't send BUS_MCEERR_AO for action required error

mm, memory_failure: don't send BUS_MCEERR_AO for action required error

Some processes dont't want to be killed early, but in "Action Required"
case, those also may be killed by BUS_MCEERR_AO when sharing memory with
other which is accessing the fail memory.  And sending SIGBUS with
BUS_MCEERR_AO for action required error is strange, so ignore the
non-current processes here.

Suggested-by: Naoya Horiguchi <[email protected]>
Signed-off-by: Wetp Zhang <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Acked-by: Naoya Horiguchi <[email protected]>
Acked-by: Pankaj Gupta <[email protected]>
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Linus Torvalds <[email protected]>