dma: ti: k3-udma: Fix ring push operation for 32 bit cores

UDMA always expects 64 bit address pointer of the transfer descriptor in
the Ring. But on 32 bit cores like R5, pointer is always 32 bit in size.
Therefore copy over 32 bit pointer value to 64 bit variable before
pushing it over to the ring, so that upper 32 bits are 0s.

Signed-off-by: Vignesh Raghavendra <vigneshr@ti.com>
Reviewed-by: Grygorii Strashko <grygorii.strashko@ti.com>
Signed-off-by: Lokesh Vutla <lokeshvutla@ti.com>