memcg: make __mod_memcg_lruvec_state re-entrant safe against irqs

Let's make __mod_memcg_lruvec_state re-entrant safe and name it
mod_memcg_lruvec_state().  The only thing needed is to convert the usage
of __this_cpu_add() to this_cpu_add().  There are two callers of
mod_memcg_lruvec_state() and one of them i.e.  __mod_objcg_mlstate() will
be re-entrant safe as well, so, rename it mod_objcg_mlstate().  The last
caller __mod_lruvec_state() still calls __mod_node_page_state() which is
not re-entrant safe yet, so keep it as is.

Link: https://lkml.kernel.org/r/20250514184158.3471331-6-shakeel.butt@linux.dev


Signed-off-by: Shakeel Butt <shakeel.butt@linux.dev>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Roman Gushchin <roman.gushchin@linux.dev>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>