CVE-2026-90271

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

arm_mpam: Fix a NULL pointer dereference on unbinding after an error interrupt

If a user unbinds an MSC after mpam_disable() has been run in response
to an error interrupt then a dereference of a NULL pointer occurs as
mpam_disable() sets the drvdata to NULL. Add an early return to the driver
remove callback to avoid this.