FreeBSD_HEAD_arm64 - Build #2584 - Fixed

[jenkins-admin at FreeBSD.org]

FreeBSD_HEAD_arm64 - Build #2584 - Fixed:

Build information: https://jenkins.FreeBSD.org/job/FreeBSD_HEAD_arm64/2584/
Full change log: https://jenkins.FreeBSD.org/job/FreeBSD_HEAD_arm64/2584/changes
Full build log: https://jenkins.FreeBSD.org/job/FreeBSD_HEAD_arm64/2584/console

Change summaries:

296676 by bdrewery:
Avoid MK_TESTS error on stable/10 by just preventing SUBDIR recursion.

296675 by bdrewery:
Avoid bmake upgrade NO_MAN warning by just setting MAN to empty.

Suggested by:	imp

296674 by dumbbell:
drm: Fix dev->ioctl_count references leak

This fixes the following error:
kernel: error: [drm:pid1167:drm_release] *ERROR* Device busy: 2

Because of that, drm_lastclose() was not called, leading to a few memory
leaks once the driver was unloaded.

MFC after:	1 week