i2c: tegra: Remove dma_sync_*() calls

Calling dma_sync_*() on a buffer from dma_alloc_coherent() is pointless.
The driver should not be doing its own bounce-buffering if the buffer is
allocated through dma_alloc_coherent().

Suggested-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Akhil R <akhilrajeev@nvidia.com>
Reviewed-by: Thierry Reding <treding@nvidia.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Andi Shyti <andi.shyti@kernel.org>
Link: https://lore.kernel.org/r/20250710131206.2316-4-akhilrajeev@nvidia.com