Always pass through VkMemoryDedicatedAllocateInfo to host

... as the host may use dedicated allocs to back the external
memory for Buffer/ColorBuffer.

Bug: b/265186355
Test: cvd start --gpu_mode=gfxstream (with AMD GPU)
Test: cvd start --gpu_mode=gfxstream (with Nvidia GPU)
Change-Id: Iba62717323d1066c5afbae32aa19961e5cf0831b
1 file changed