dmaengine: ti: k3-udma: Fix BCHAN count with UHC and HC channels

Unlike other channel counts in CAPx registers, BCDMA BCHAN CNT doesn't
include UHC and HC BC channels. So include them explicitly to arrive at
total BC channel in the instance.

Fixes: 88448980

 ("dmaengine: ti: k3-udma: Add support for BCDMA channel TPL handling")
Signed-off-by: Vignesh Raghavendra <vigneshr@ti.com>
Signed-off-by: Jai Luthra <j-luthra@ti.com>
Tested-by: Jayesh Choudhary <j-choudhary@ti.com>
Link: https://lore.kernel.org/r/20240607-bcdma_chan_cnt-v2-1-bf1a55529d91@ti.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>