mm/damon/sysfs-scheme: cleanup access_pattern subdirs on scheme dir setup failure

In the Linux kernel, the following vulnerability has been resolved:

mm/damon/sysfs-scheme: cleanup access_pattern subdirs on scheme dir setup failure

When a DAMOS-scheme DAMON sysfs directory setup fails after setup of

access_pattern/ directory, subdirectories of access_pattern/ directory are

not cleaned up. As a result, DAMON sysfs interface is nearly broken until

the system reboots, and the memory for the unremoved directory is leaked.

Cleanup the directories under such failures.