net: phy: Fix WOL in Micrel phy

Generic Phy Resume/Suspend API's already hold the mutex and
holding the mutex in Micrel will cause a deadlock.
Make a change to remove the  mutex locks in Micrel code.

Change-Id: Ib3bd976dc70f7669ee1e34658b565921d6704e25
Signed-off-by: Suraj Jaiswal <jsuraj@codeaurora.org>