5255 uts shouldn't open-code ISP2

*** 21,30 ****
--- 21,31 ----
  /*
   * Copyright 2009 Sun Microsystems, Inc.  All rights reserved.
   * Use is subject to license terms.
   */
  
+ #include <sys/sysmacros.h>
  #include <sys/systm.h>
  #include <sys/param.h>
  #include <sys/debug.h>
  #include <sys/kmem.h>
  #include <sys/group.h>
*** 129,140 ****
          g->grp_set[i] = NULL;
          group_pack_set(g->grp_set, g->grp_size);
          g->grp_size--;
  
          if ((gflag & GRP_RESIZE) &&
!             g->grp_size > GRP_SET_SIZE_DEFAULT &&
!             ((g->grp_size - 1) & g->grp_size) == 0)
                  group_shrink_set(g);
  
          return (0);
  }
  
--- 130,140 ----
          g->grp_set[i] = NULL;
          group_pack_set(g->grp_set, g->grp_size);
          g->grp_size--;
  
          if ((gflag & GRP_RESIZE) &&
!             g->grp_size > GRP_SET_SIZE_DEFAULT && ISP2(g->grp_size))
                  group_shrink_set(g);
  
          return (0);
  }