msm: kgsl: Fix gpu boot ab vote

The ab is in megabytes and ddr_table is in kilobytes. So do
the conversion to fix the first ab vote out of slumber.

Also fix the ib vote units for the very first gmu boot.

Change-Id: I57efd80fa2de8262842475e02a363e0436a7b0f2
Signed-off-by: Harshdeep Dhatt <hdhatt@codeaurora.org>