From NetBSD, from FreeBSD (as nvmecontrol)

Since we don't create separate devices for NVMe controllers, ioctl
access goes through the disk device (e.g., nvmectl identify /dev/sd0c)

The X1 Nano can usually cruise with no fan on during most normal
activity, but the EC has this temperature threshold set a tad too
low so it constantly toggles the fan between off and running at its
lowest speed. Do this manually in the acpithinkpad driver but bump
the temperature threshold up a bit to stop it from turning on unless
needed.

ok kn

This reverts commit bf9a317d19824ee8094e0b4d59231240363f3c05.

For some reason 60Hz doesn't work properly, so prefer 48Hz until I
can figure out why.