msm: emac: Fix dynamic unloading of emac module

Due to unstable clock vote the unload part of
emac module is not successful and causing
unclock error while loading again.

Fix the crash while dynamically unloading and loading
of emac module.

Change-Id: I45883bddc26cffcbdd4120033e970d8f59ee7872
Signed-off-by: Alok Chauhan <alokc@codeaurora.org>