[SYCL] Remove FPGA metadata kernel_arg_buffer_location (#22499)
The metadata was introduced for FPGA in 0c38b3595d26 (#2166). FPGA
support was already removed from DPC++ (#16929). Drop it to avoid
polluting LIT checks.
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Co-authored-by: Claude Sonnet 4.6 <noreply@anthropic.com>
