MFC: 1.22
MFC: 1.22

- Don't set MIIF_NOISOLATE so tdkphy(4) can be used in configurations
  with multiple PHYs. There doesn't seem to be a problem with isolating
  78Q2120 per se nor in combination with the NICs they're used with and
  tdkphy(4) was already adding IFM_NONE anyway.
- Set MIIF_NOLOOP as loopback doesn't work with this PHY. The MIIF_NOLOOP
  flag currently triggers nothing but hopefully will be respected by
  mii_phy_setmedia() later on.
- Use mii_phy_add_media() instead of mii_add_media() so the latter can
  be eventually retired.
- Take advantage of mii_phy_setmedia().

Thanks to Hans-Joerg Sirtl for lending me test hardware.

Obtained from:	NetBSD tqphy(4)

jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase