- Allow indirect heap to work in 2 modes:
first mode is when it will be used as an allocation from 4GB allocator.
In such scenario driver will return offset from base of the allocator region.
Second mode is the legacy mode which will be used by device enqueue, this
will results in heap CPU base address being programmed in State Base Address
commands and during programming heap offset base of 0 will be returned.
Change-Id: Ica098f3278b6b6ed5036b4c5ab7461dc61d8ee86