OS-2366 ddi_periodic_add(9F) is entirely rubbish

*** 2243,2260 ****
  
          (void) add_avsoftintr((void *)&softlevel1_hdl, 1, softlevel1,
              "softlevel1", NULL, NULL); /* XXX to be moved later */
  
          /*
!          * Register these software interrupts for ddi timer.
           * Software interrupts up to the level 10 are supported.
           */
          for (i = DDI_IPL_1; i <= DDI_IPL_10; i++) {
!                 char name[sizeof ("timer_softintr") + 2];
!                 (void) sprintf(name, "timer_softintr%02d", i);
                  (void) add_avsoftintr((void *)&softlevel_hdl[i-1], i,
!                     (avfunc)timer_softintr, name, (caddr_t)(uintptr_t)i, NULL);
          }
  
  #if !defined(__xpv)
          if (modload("drv", "amd_iommu") < 0) {
                  PRM_POINT("No AMD IOMMU present\n");
--- 2243,2264 ----
  
          (void) add_avsoftintr((void *)&softlevel1_hdl, 1, softlevel1,
              "softlevel1", NULL, NULL); /* XXX to be moved later */
  
          /*
!          * Register software interrupt handlers for ddi_periodic_add(9F).
           * Software interrupts up to the level 10 are supported.
           */
          for (i = DDI_IPL_1; i <= DDI_IPL_10; i++) {
!                 /*
!                  * The constant string "ddi_periodic", below, is only used to
!                  * print debugging information.  Generating a dynamic string
!                  * for each soft level is a waste of kernel memory.
!                  */
                  (void) add_avsoftintr((void *)&softlevel_hdl[i-1], i,
!                     (avfunc)ddi_periodic_softintr, "ddi_periodic",
!                     (caddr_t)(uintptr_t)i, NULL);
          }
  
  #if !defined(__xpv)
          if (modload("drv", "amd_iommu") < 0) {
                  PRM_POINT("No AMD IOMMU present\n");