While Qualcomm Snapdragon X Elite (X1E80100) claims to support 32 device-id

While Qualcomm Snapdragon X Elite (X1E80100) claims to support 32 device-id
bits, it only seems to allow a 4k pagesize with 8 bytes per entry.  This is
not enough to handle all 32 device-id bits, but we also don't necessarily
need to handle all of them.  Hence clamp down the number of maximum device
IDs to as much as we can possibly configure in hardware.

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