switch: a38x: add SOHO switch support

	- Implement basic switch reg read/write interfaces for neta(including
	  smi-multi-addr access mode and not smi-multi-addr access mode)
	- Add detection function for neta switch to get switch device ID and
	  access mode
	- Add 6172 switch basic init function
	- For SOHO switch neta board, force the connected phy port link up
	- Add fdt updates for u-boot initialization
	- Add switch information to a38x board info

Change-Id: I492a3d34de1fdcc71736d85739d52729c379d759
Signed-off-by: Ken Ma <make@marvell.com>
Reviewed-on: http://vgitil04.il.marvell.com:8080/17140
Reviewed-by: Omri Itach <omrii@marvell.com>
Tested-by: Omri Itach <omrii@marvell.com>
19 files changed