msm vidc: Fixed memory leak in venus core init

In venus core init bus_vote object is allocated on
the heap, which is overwritten in consecutive call
for init bus without freeing the original object.
Fix was to remove the default initialization during
init bus.

Change-Id: I007e6363327a32c4fd66bcaf02199fe627a4260f
Signed-off-by: SaiVamshi Dobbali <sdobbali@codeaurora.org>