drm/panthor: Fix kerneldoc in uAPI header

drm/panthor: Fix kerneldoc in uAPI header

Fix a typo in a kerneldoc header.

Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Closes: https://lore.kernel.org/dri-devel/20251216120049.3ed7e06e@canb.auug.org.au/
Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
Reviewed-by: Liviu Dudau <liviu.dudau@arm.com>
Reviewed-by: Steven Price <steven.price@arm.com>
Fixes: ea78ec982653 ("drm/panthor: Expose the selected coherency protocol to the UMD")
Signed-off-by: Steven Price <steven.price@arm.com>
Link: https://patch.msgid.link/20251217132403.3996014-1-boris.brezillon@collabora.com