drm/xe: Make irq enabled flag atomic

The irq.enabled flag was protected by a spin lock (irq.lock).
By making it atomic we no longer need to wait for the spin lock in
irq handlers. This will become especially useful for MSI-X irq
handlers to prevent lock contention between different interrupts.

Signed-off-by: Ilia Levi <ilia.levi@intel.com>
Reviewed-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20241210173506.202150-1-ilia.levi@intel.com


Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>