drm/ttm: Remove unneeded blank line in comment

drm/ttm: Remove unneeded blank line in comment

There is an unneeded blank line in the documentation of the function
ttm_bo_kmap_try_from_panic().

Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202506290453.NeTXAb7S-lkp@intel.com/
Fixes: 718370ff28328 ("drm/ttm: Add ttm_bo_kmap_try_from_panic()")
Signed-off-by: Jocelyn Falempe <jfalempe@redhat.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
Link: https://lore.kernel.org/r/20250630144154.44661-1-jfalempe@redhat.com
Signed-off-by: Lucas De Marchi <lucas.demarchi@intel.com>