NXP RT series DMA need use buffer in nocached area,
so only use memory region relocated is not enough.
fixing: #67053
Signed-off-by: Hake Huang <hake.huang@oss.nxp.com>
Convert test to use DEVICE_DT_GET via a nodelabel.
Introduce a test_dma devicetree nodelabel to reference the DMA
controller the test should use.
Signed-off-by: Kumar Gala <galak@kernel.org>