mm/damon: add kernel-doc comment for damos_filter->sz_range

mm/damon: add kernel-doc comment for damos_filter->sz_range

Commit 212f4d0cb42c ("mm/damon: introduce DAMOS filter type
hugepage_size") on mm-unstable added sz_range field to 'struct
damos_filter'.  It missed updating the kernel-doc comment, though.  It is
making the documentation build unhappy.  Add a comment for the field.

Link: https://lkml.kernel.org/r/20250218223058.52459-1-sj@kernel.org
Fixes: 212f4d0cb42c ("mm/damon: introduce DAMOS filter type hugepage_size") # mm-unstable
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: Usama Arif <usamaarif642@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>