net: dsa: sja1105: add support for the SJA1110 switch family

The SJA1110 is basically an SJA1105 with more ports, some integrated
PHYs (100base-T1 and 100base-TX) and an embedded microcontroller which
can be disabled, and the switch core can be controlled by a host running
Linux, over SPI.

This patch contains:
- the static and dynamic config packing functions, for the tables that
  are common with SJA1105
- one more static config tables which is "unique" to the SJA1110
  (actually it is a rehash of stuff that was placed somewhere else in
  SJA1105): the PCP Remapping Table
- a reset and clock configuration procedure for the SJA1110 switch.
  This resets just the switch subsystem, and gates off the clock which
  powers on the embedded microcontroller.
- an RGMII delay configuration procedure for SJA1110, which is very
  similar to SJA1105, but different enough for us to be unable to reuse
  it (this is a pattern that repeats itself)
- some adaptations to dynamic config table entries which are no longer
  programmed in the same way. For example, to delete a VLAN, you used to
  write an entry through the dynamic reconfiguration interface with the
  desired VLAN ID, and with the VALIDENT bit set to false. Now, the VLAN
  table entries contain a TYPE_ENTRY field, which must be set to zero
  (in a backwards-incompatible way) in order for the entry to be deleted,
  or to some other entry for the VLAN to match "inner tagged" or "outer
  tagged" packets.
- a similar thing for the static config: the xMII Mode Parameters Table
  encoding for SGMII and MII (the latter just when attached to a
  100base-TX PHY) just isn't what it used to be in SJA1105. They are
  identical, except there is an extra "special" bit which needs to be
  set. Set it.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>