cgem: improve usage of busdma(9) KPI
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Authored by mhorne on Feb 18 2021, 5:11 PM.

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mmel
skibo

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rG04d2d2d7fd22: cgem: improve usage of busdma(9) KPI

Summary

BUS_DMA_NOCACHE should only be used when one needs to guarantee the
created mapping has uncached memory attributes, usually as a result of buggy
hardware. Normal use cases should pass BUS_DMA_COHERENT, to create an
appropriate mapping based on the flags passed to bus_dma_tag_create().

This should have no functional change, since the DMA tags in this driver are
created without the BUS_DMA_COHERENT flag.

Reported by: mmel