audit: hand taken context to audit_kill_trees for syscall logging

audit: hand taken context to audit_kill_trees for syscall logging

Since the context is derived from the task parameter handed to
__audit_free(), hand the context to audit_kill_trees() so it can be used
to associate with a syscall record.  This requires adding the context
parameter to kill_rules() rather than using the current audit_context.

The callers of trim_marked() and evict_chunk() still have their context.

The EOE record was being issued prior to the pruning of the killed_tree
list.

Move the kill_trees call before the audit_log_exit call in
__audit_free() and __audit_syscall_exit() so that any pruned trees
CONFIG_CHANGE records are included with the associated syscall event by
the user library due to the EOE record flagging the end of the event.

See: https://github.com/linux-audit/audit-kernel/issues/50
See: https://github.com/linux-audit/audit-kernel/issues/59

Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
[PM: fixed merge fuzz in kernel/audit_tree.c]
Signed-off-by: Paul Moore <paul@paul-moore.com>