Graphics/drm-fbsd11.2-kmod: Update snapshot

Update graphics/drm-fbsd11.2-kmod to the latest snapshot.
Make unsynchronized DRM_IOCTL_I915_GEM_USERPTR work in mesa on 7th
generation Haswell graphics. This is needed for vulkan.
Add devctl (devd) notification for monitor hotplug.

MFH: 2020Q1 (implicit, drm-drivers blanket)