phy: cadence: cdns-dphy: Enable lower resolutions in dphy

phy: cadence: cdns-dphy: Enable lower resolutions in dphy

Enable support for data lane rates between 80-160 Mbps cdns dphy
as mentioned in TRM [0] by setting the pll_opdiv field to 16.
This change enables lower resolutions like 640x480 at 60Hz.

[0]: https://www.ti.com/lit/zip/spruil1
(Table 12-552. DPHY_TX_PLL_CTRL Register Field Descriptions)

Reviewed-by: Udit Kumar <u-kumar1@ti.com>
Reviewed-by: Devarsh Thakkar <devarsht@ti.com>
Signed-off-by: Harikrishna Shenoy <h-shenoy@ti.com>
Link: https://lore.kernel.org/r/20250807052002.717807-1-h-shenoy@ti.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>