CVE-2026-68180: intel_th: fix MSC output device reference leak

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

intelth: fix MSC output device reference leak

intelthoutputopen() looks up the output device with busfinddevicebydevt(), which returns the device with a reference that must be dropped after use.

commit 95fc36a234da ("intelth: fix device leak on output open()") attempted to drop the reference from intelthoutputrelease(). However, a successful open replaces file->fop with the output driver file operations before returning, so close runs the output driver release callback instead.

For MSC outputs, close runs intelthmscrelease(), which only removes the per-file iterator and does not drop the device reference taken by intelthoutputopen(). Consequently, every successful MSC output open leaks one device reference.

Drop the device reference from intelthmscrelease(), which is the release path actually used for MSC output files. Remove the now-unused intelthoutputrelease() callback from intelthoutputfops.