Update mg_check_ip_acl.md

docs/c-api/net.h/mg_check_ip_acl.md

@@ -13,7 +13,7 @@ Verifies given IP address against the ACL.
 Each subnet is
 prepended by either a - or a + sign. A plus sign means allow, where a
 minus sign means deny. If a subnet mask is omitted, such as `-1.2.3.4`,
-this means to deny only that single IP address.
+it means that only that single IP address is denied.
 Subnet masks may vary from 0 to 32, inclusive. The default setting
 is to allow all access. On each request the full list is traversed,
 and the last match wins. Example: