drm/xe/uapi: Fix kernel-doc formatting for madvise and vma_query

Correct kernel-doc formatting issues in the UAPI definitions for
madvise and VMA query interfaces to resolve docutils warnings during
documentation build.

Fixes: 41880786 ("drm/xe/uapi: Add UAPI for querying VMA count and memory attributes")
Fixes: 231bb0ee ("drm/xe/uapi: Add madvise interface")
Cc: Matthew Brost <matthew.brost@intel.com>
Cc: Lucas De Marchi <lucas.demarchi@intel.com>
Signed-off-by: Himal Prasad Ghimiray <himal.prasad.ghimiray@intel.com>
Reviewed-by: Lucas De Marchi <lucas.demarchi@intel.com>
Link: https://lore.kernel.org/r/20250828071516.3838110-1-himal.prasad.ghimiray@intel.com


Signed-off-by: Lucas De Marchi <lucas.demarchi@intel.com>