venus: add logging and raise VKR_CS_DECODER_TEMP_POOL_MAX_SIZE to 1GB
VKR_CS_DECODER_TEMP_POOL_MAX_SIZE is to avoid integer overflows and to catch bogus allocations (e.g.,
the guest driver encodes an uninitialized value). In practice, the largest
allocations we've seen are from vkGetPipelineCacheData and are dozens of
MBs.
This fixes Rise of the Tomb Raider whose vkGetPipelineCacheData calls can exceed 32MB.