OS-1573 vnic_dev.c insufficiently explicit

*** 50,59 ****
--- 50,60 ----
  #include <sys/pattr.h>
  #include <sys/time.h>
  #include <sys/vlan.h>
  #include <sys/vnic.h>
  #include <sys/vnic_impl.h>
+ #include <sys/mac_impl.h>
  #include <sys/mac_flow_impl.h>
  #include <inet/ip_impl.h>
  
  /*
   * Note that for best performance, the VNIC is a passthrough design.
*** 845,864 ****
  /*ARGSUSED*/
  static int
  vnic_m_setprop(void *m_driver, const char *pr_name, mac_prop_id_t pr_num,
      uint_t pr_valsize, const void *pr_val)
  {
!         int             err = ENOTSUP;
          vnic_t          *vn = m_driver;
  
          switch (pr_num) {
          case MAC_PROP_MTU: {
                  uint32_t        mtu;
  
                  /* allow setting MTU only on an etherstub */
!                 if (vn->vn_link_id != DATALINK_INVALID_LINKID)
!                         return (err);
  
                  if (pr_valsize < sizeof (mtu)) {
                          err = EINVAL;
                          break;
                  }
--- 846,867 ----
  /*ARGSUSED*/
  static int
  vnic_m_setprop(void *m_driver, const char *pr_name, mac_prop_id_t pr_num,
      uint_t pr_valsize, const void *pr_val)
  {
!         int             err = 0;
          vnic_t          *vn = m_driver;
  
          switch (pr_num) {
          case MAC_PROP_MTU: {
                  uint32_t        mtu;
  
                  /* allow setting MTU only on an etherstub */
!                 if (vn->vn_link_id != DATALINK_INVALID_LINKID) {
!                         err = ENOTSUP;
!                         break;
!                 }
  
                  if (pr_valsize < sizeof (mtu)) {
                          err = EINVAL;
                          break;
                  }
*** 877,889 ****
                          err = EINVAL;
                          break;
                  }
  
                  bcopy(pr_val, &filtered, sizeof (filtered));
!                 err = mac_set_promisc_filtered(vn->vn_mch, filtered);
          }
          default:
                  break;
          }
          return (err);
  }
  
--- 880,893 ----
                          err = EINVAL;
                          break;
                  }
  
                  bcopy(pr_val, &filtered, sizeof (filtered));
!                 mac_set_promisc_filtered(vn->vn_mch, filtered);
          }
          default:
+                 err = ENOTSUP;
                  break;
          }
          return (err);
  }