netfilter: ipset: Remove unused htable_bits in macro ahash_region

Since the ahash_region() macro was redefined to calculate the region
index solely from HTABLE_REGION_BITS, the htable_bits parameter became
unused.

Remove the unused htable_bits argument and its call sites, simplifying
the code without changing semantics.

Fixes: 8478a729c046 ("netfilter: ipset: fix region locking in hash types")
Signed-off-by: Zhen Ni <[e-mail]>
Reviewed-by: Phil Sutter <[e-mail]>
Signed-off-by: Florian Westphal <[e-mail]>

net/netfilter/ipset/ip_set_hash_gen.h

···
 		: jhash_size((htable_bits) - HTABLE_REGION_BITS))
 #define ahash_sizeof_regions(htable_bits)		\
 	(ahash_numof_locks(htable_bits) * sizeof(struct ip_set_region))
-#define ahash_region(n, htable_bits)		\
+#define ahash_region(n)		\
 	((n) / jhash_size(HTABLE_REGION_BITS))
 #define ahash_bucket_start(h,  htable_bits)	\
 	((htable_bits) < HTABLE_REGION_BITS ? 0	\
···
 #endif
 				key = HKEY(data, h->initval, htable_bits);
 				m = __ipset_dereference(hbucket(t, key));
-				nr = ahash_region(key, htable_bits);
+				nr = ahash_region(key);
 				if (!m) {
 					m = kzalloc(sizeof(*m) +
 					    AHASH_INIT_SIZE * dsize,
···
 	rcu_read_lock_bh();
 	t = rcu_dereference_bh(h->table);
 	key = HKEY(value, h->initval, t->htable_bits);
-	r = ahash_region(key, t->htable_bits);
+	r = ahash_region(key);
 	atomic_inc(&t->uref);
 	elements = t->hregion[r].elements;
 	maxelem = t->maxelem;
···
 	rcu_read_lock_bh();
 	t = rcu_dereference_bh(h->table);
 	key = HKEY(value, h->initval, t->htable_bits);
-	r = ahash_region(key, t->htable_bits);
+	r = ahash_region(key);
 	atomic_inc(&t->uref);
 	rcu_read_unlock_bh();