atm: idt77252: Add missing `dma_map_error()`

[ Upstream commit c4890963350dcf4e9a909bae23665921fba4ad27 ]

The DMA map functions can fail and should be tested for errors.

Signed-off-by: Thomas Fourier <fourier.thomas@gmail.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/20250624064148.12815-3-fourier.thomas@gmail.com


Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>