gh-123465: Ensure PyType_FromMetaclass avoids extra strcmp (GH-125460)

use else

Author: neonene

Objects/typeobject.c

@@ -4761,10 +4761,10 @@ PyType_FromMetaclass(
                 if (strcmp(memb->name, "__weaklistoffset__") == 0) {
                     weaklistoffset_member = memb;
                 }
-                if (strcmp(memb->name, "__dictoffset__") == 0) {
+                else if (strcmp(memb->name, "__dictoffset__") == 0) {
                     dictoffset_member = memb;
                 }
-                if (strcmp(memb->name, "__vectorcalloffset__") == 0) {
+                else if (strcmp(memb->name, "__vectorcalloffset__") == 0) {
                     vectorcalloffset_member = memb;
                 }
             }