msm: emac: Fix crash during unloading of emac module

Due to wrong ephy id check the phy connect/disconnect
sequence is going out of sync and causing crash while
unloading of emac driver module. Lower MDIO clock
rate also causes emac to not communicate properly.

Add the correct ephy id check and change MDIO clock rate.

Change-Id: If72addc91a6e5ecba1e697338fe76047976e8b38
Signed-off-by: Alok Chauhan <alokc@codeaurora.org>