hw/dma/omap_dma: Remove support for dma_3_0 and dma_3_2

hw/dma/omap_dma: Remove support for dma_3_0 and dma_3_2

The omap_dma device has support for modelling different variants
of the DMA block, as enumerated by the omap_dma_model enum:
3_0, 3_1 and 3_2. However, our one remaining OMAP SoC always
passes omap_dma_3_1 into the omap_dma_init() function, so the
handling for 3_0 and 3_2 is never used.

Remove the support for the other versions; this lets us
delete entirely two large functions that were specific
to 3.2 DMA to the LCD controller, and all their associated
fields in the omap_dma_lcd_channel_s struct.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20260512203414.3633237-8-peter.maydell@linaro.org