Merge branch 'dp83867-impedance-control'

Mugunthan V N says:

====================
add support for impedance control for TI dp83867 phy and fix 2nd ethernet on dra72 rev C evm

Add support for configurable impedance control for TI dp83867
phy via devicetree. More documentation in [1].
CPSW second ethernet is not working, fix it by enabling
impedance configuration on the phy.

Verified the patch on DRA72 Rev C evm, logs at [2]. Also pushed
a branch [3] for others to test.

Changes from v3:
* Fixup change log text and no code changes.

Changes from v2:
* Fixed a typo in dts and driver.

Changes from initial version:
* As per Sekhar's comment, instead of passing impedance values,
  change to max and min impedance from DT
* Adopted phy_read_mmd_indirect() to cunnrent implementation.
* Corrected the phy delay timings to the optimal value.

[1] - http://www.ti.com/lit/ds/symlink/dp83867ir.pdf
[2] - http://pastebin.ubuntu.com/23343139/
[3] - git://git.ti.com/~mugunthanvnm/ti-linux-kernel/linux.git dp83867-v4
====================

Signed-off-by: David S. Miller <davem@davemloft.net>