dmaengine: ti: k3-psil-am62: Fix SPI PDMA data

AM62x has 3 SPI channels where each channel has 4 TX and 4 RX threads.
This also fixes the thread numbers.

Signed-off-by: Ronald Wahl <ronald.wahl@raritan.com>
Fixes: 5ac6bfb5

 ("dmaengine: ti: k3-psil: Add AM62x PSIL and PDMA data")
Reviewed-by: Jai Luthra <j-luthra@ti.com>
Acked-by: Peter Ujfalusi <peter.ujfalusi@gmail.com>
Link: https://lore.kernel.org/r/20231030190113.16782-1-rwahl@gmx.de
Signed-off-by: Vinod Koul <vkoul@kernel.org>