ARM: dts: msm: EMAC phy addr

This change add support to provide the phy address in dtsi file
so that it can be used for early ethernet for fast phy detection.

Change-Id: Ib05d9bc2a57274f87b1bb803fc4e68da1b2a34b0
Signed-off-by: Suraj Jaiswal <jsuraj@codeaurora.org>