Always prefer device_reads when kvikio is enabled

[vuule]

Description

Issue #17259

Avoid checking _gds_read_preferred_threshold threshold when deciding whether device_read is preferred to host_read + H2D copy. The reasons are twofold:

1. KvikIO already has an internal threshold for GDS use so we don't need to check on our end as well.
2. Without actual GDS use, kvikIO uses a pinned bounce buffer to efficiently copy to the device.

Checklist

• I am familiar with the Contributing Guidelines.
• New or existing tests cover these changes.
• The documentation is up to date with these changes.