5042 stop using deprecated atomic functions

*** 21,32 ****
  /*
   * Copyright 2008 Sun Microsystems, Inc.  All rights reserved.
   * Use is subject to license terms.
   */
  
- #pragma ident   "%Z%%M% %I%     %E% SMI"
- 
  #include <sys/types.h>
  #include <sys/param.h>
  #include <sys/cmn_err.h>
  #include <sys/mutex.h>
  #include <sys/systm.h>
--- 21,30 ----
*** 271,281 ****
                           * preemption and see if we should sleep.  If we are
                           * already the lock holder, remove the effect of the
                           * previous kpreempt_disable() before returning since
                           * preemption was disabled by an earlier kern_preprom.
                           */
!                         prcp = casptr((void *)&prom_cpu, NULL, cp);
                          if (prcp == NULL ||
                              (prcp == cp && prom_thread == curthread)) {
                                  if (prcp == cp)
                                          kpreempt_enable();
                                  break;
--- 269,279 ----
                           * preemption and see if we should sleep.  If we are
                           * already the lock holder, remove the effect of the
                           * previous kpreempt_disable() before returning since
                           * preemption was disabled by an earlier kern_preprom.
                           */
!                         prcp = atomic_cas_ptr((void *)&prom_cpu, NULL, cp);
                          if (prcp == NULL ||
                              (prcp == cp && prom_thread == curthread)) {
                                  if (prcp == cp)
                                          kpreempt_enable();
                                  break;
*** 308,318 ****
                          /*
                           * If we are not yet mutex_ready, just attempt to grab
                           * the lock.  If we get it or already hold it, break.
                           */
                          ASSERT(getpil() == PIL_MAX);
!                         prcp = casptr((void *)&prom_cpu, NULL, cp);
                          if (prcp == NULL || prcp == cp)
                                  break;
                  }
          }
  
--- 306,316 ----
                          /*
                           * If we are not yet mutex_ready, just attempt to grab
                           * the lock.  If we get it or already hold it, break.
                           */
                          ASSERT(getpil() == PIL_MAX);
!                         prcp = atomic_cas_ptr((void *)&prom_cpu, NULL, cp);
                          if (prcp == NULL || prcp == cp)
                                  break;
                  }
          }