Allocate SVM address space for the registered memory and use new
userptr support in KFD to create a system memory BO associated with
the given user pointer. Map this BO at the SVM address for CPU
access.
MapMemoryToGPU can be used with the registered user pointer and
will return the SVM address as alternate GPUVA.
Change-Id: I4886e193c51fb6870a567878870c36bf8b5c3748
Fix hsaKmtRegisterMemory to be a no-op for now and move the multi-GPU
implementation to hsaKmtRegisterMemoryToNodes. Make GPU memory mappings
of host memory visible to all GPUs by default. Device memory is still
visible to the allocating GPU only by default (but can be overridden
with hsaKmtRegisterMemoryToNodes for experimenting with P2P).
Change-Id: I73408afbe3b10c8dad2ab3a780f58413249692e6