spi: meson-spicc: add DMA support

spi: meson-spicc: add DMA support

Add DMA support for spicc driver.

DMA works if the transfer meets the following conditions:
1. 64 bits per word;
2. The transfer length must be multiples of the dma_burst_len,
   and the dma_burst_len should be one of 8,7...2,
   otherwise, it will be split into several SPI bursts.

Signed-off-by: Sunny Luo <sunny.luo@amlogic.com>
Signed-off-by: Xianwei Zhao <xianwei.zhao@amlogic.com>
Link: https://patch.msgid.link/20250414-spi-dma-v2-1-84bbd92fa469@amlogic.com
Signed-off-by: Mark Brown <broonie@kernel.org>