oom fix: prevent oom from killing a process with children/sibling unkillable

oom fix: prevent oom from killing a process with children/sibling unkillable

Looking at oom_kill.c, found that the intention to not kill the selected
process if any of its children/siblings has OOM_DISABLE set, is not being
met.

Signed-off-by: Ankita Garg <ankita@in.ibm.com>
Cc: Chuck Ebbert <cebbert@redhat.com>
Acked-by: Nick Piggin <npiggin@suse.de>
Acked-by: William Irwin <wli@holomorphy.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>