5042 stop using deprecated atomic functions

@@ -165,11 +165,11 @@
                 do {
                         old = panicbuf_index;
                         new = old + len;
                         if (new >= PANICBUFSIZE)
                                 new = panicbuf_log + len;
-                } while (cas32(&panicbuf_index, old, new) != old);
+                } while (atomic_cas_32(&panicbuf_index, old, new) != old);
                 bcopy(body, &panicbuf[new - len], len);
         }
         if (bufp != buf)
                 kmem_free(bufp, bufsize);
 }