mm/mempolicy: count MPOL_WEIGHTED_INTERLEAVE to "interleave_hit"

Commit fa3bea4e introduced MPOL_WEIGHTED_INTERLEAVE but it missed
adding its counter to "interleave_hit" of numastat, which is located at
/sys/devices/system/node/nodeN/ directory.

It'd be better to add weighted interleving counter info to the existing
"interleave_hit" instead of introducing a new counter
"weighted_interleave_hit".

Link: https://lkml.kernel.org/r/20241227095737.645-1-honggyu.kim@sk.com


Fixes: fa3bea4e ("mm/mempolicy: introduce MPOL_WEIGHTED_INTERLEAVE for weighted interleaving")
Signed-off-by: Honggyu Kim <honggyu.kim@sk.com>
Reviewed-by: Gregory Price <gourry@gourry.net>
Reviewed-by: Hyeonggon Yoo <hyeonggon.yoo@sk.com>
Tested-by: Yunjeong Mun <yunjeong.mun@sk.com>
Cc: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>